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Old 08-16-2013, 04:27 PM   #121
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last one...

Long story short, I drove like crap and wasn't well prepared for this event. Our 8 time ESP National Champion, Mark Madarash, was there in his flyweight Firebird and he schooled the entire ESP class, taking the win and setting Top PAX for the event as well, using only four of his allotted five runs. I fumbled my way through all five runs - getting lost, blowing corners, late into slaloms, DNF'd, double-apexing turns, and generally driving like a total ass hat. On my fifth run I almost put one together, but still lost the brake booster into two turns and blew my lines. Would I have caught Madarash with a miracle hero run? Probably wasn't going to happen, even with a better driver. Our Mustang is still 400 pounds too heavy and needs a lot more to keep up with that proven ESP winner.



The issues we had were also too numerous to count. The brake booster assist failure cropped up for me on all five runs, so that lovely problem has returned. We have yet another replacement vacuum check valve coming from Ford (and another as a spare!) as this seemed to fix the problem after the Optima event in June, where it was a big hindrance.


In-car from my 5th and fastest run is linked above. It is still terrible.

Might not seem like a big deal - losing the vacuum assist - but in this car when the booster goes away, suddenly it really throws you for a loop and blows your concentration. The pedal works fine, but after a long straight with high rpm usage it would intermittently lose assist and you felt like you were stepping on a brick, the pedal doesn't move, and the car won't stop. It wasn't consistent, but it did happen to me on every run.


Looks like much less lean here than at Nationals thanks to the new, stiffer spring rates.

When this happened at the Optima Challenge I luckily had a dozen autocross runs to put one together, and many laps on track to adjust my braking zones. You have to press the brake pedal with both feet and PULL on the steering wheel to get enough pedal movement to stop. It was exhausting at ECR back in June, but after we replaced the check valve in the booster it went away completely at the next ECR event in late June. So... just like the S197 front wheel hubs (we're on the third set in two years), the vacuum booster check valve has become a wear item, with spares to be kept in the race trailer. Live and learn.


Amy's 5th and fastest run is linked above.

Amy had a pretty good day, finishing third in class and 25th out of 126 in PAX, but she was a solid 1.4 seconds back from me. Just not driving aggressively enough? She got caught out by the slick spots and slalom timing on her best run also, but as always she still looks a lot smoother and cleaner than my hack driving runs. She is adjusting from street tire to R compound grip, slowly but surely. We need to keep getting her more and more seat time - when we all ran in STU for years she would regularly be on the same half second as Brian and I.

I think I need to avoid racing on three consecutive 100 degree days. I never do well in that type of prolonged heat. By Sunday I was sporting a massive headache and muscle aches, which meant I was low on water and salts. Stupid mistakes were abundant. As well as I felt that I drove on Friday and Saturday, I more than made up for it on Sunday with terrible driving. I really wanted to run GTA and this SCCA event, but probably shouldn't have done both.

What's Next?

This weekend, October 6th-7th, is the annual NASA race weekend at Eagles Canyon Raceway - which is what I consider my "home track". We had planned on running the red 2011 GT in TTS and the blue BMW E46 330Ci in TTD, but alas, the painter was delayed and the E46 will not be ready in time. Sucks, because we had run times 3+ seconds quicker than the old record (set by Costas in this same BMW in 2010, on street tires) with the 285 Hoosier R6s we can run in that class. Oh well, we will run the black 2013 GT in TTB (and get slaughtered) and the red 2011 GT in TTS and just have fun. I could get lucky and beat the existing TTS record at ECR (1:58.2), as I ran almost that quick back in June on the old Kumho's with the steering shudder and the old clanking PHB, but who knows? If fast Corvettes show up or the existing 350Z record holder are there, I'm sure they will be shooting to beat that record, too.

After the NASA weekend is a SCCA Club Race and PDX event on October 13th-14th. We had entered both Mustangs for that HPDE-like event, but will likely run the 2011 and the blue BMW there instead. Once the blue BMW gets back from its fresh paint job and gets some on-track laps/video/data, we will put it up for sale. We never drive this car and with seven cars and only room for six at our home garage, we need to "reduce the fleet".



I also have to get caught up on some pictures and text for the initial 2013 GT "ESP" thread. We have already done a lot of weighing and planning, parts are some coming, we have 18x10s on the car, and camber plates are going on today.

More soon!
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Old 08-16-2013, 04:28 PM   #122
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Project Update for Oct 11, 2012: We drove both the 2011 and 2013 Mustang GT's at last weekend's NASA Time Trial event at Eagles canyon Raceway (ECR). I had planned to wait after this coming weekend's SCCA Club Race/PDX event but they cancelled it, so I will share what we have learned now instead. I'm still writing the 2013's first post in its own thread, but it is coming soon. We also did some dyno pulls on both Mustangs and the 2013 BRZ yesterday at True Street Motorsports, so I can share those as well.

Pre-Race Prep

As mentioned in my last post the '11 GT needed surprisingly little prep before this NASA race weekend. We had just run it at the Global Time Attack and a local autocross just 2 weeks prior and all of the then newly added Whiteline rear suspension bits were working perfectly - and with two weeks of silent street use we were all smiles. Other than two more new Kumho V710 tires, an oil/filter change, and the swap back to the winged trunk and race tires, it was an easy prep.



That shot above shows all of the Whiteline goodies. These changes + the slight bump in spring rates are all that were different from the car in June when we ran ECR and I knocked off a 1:58.2 lap, using Hanchey's AIM Solo in-car lap timer. We were back to running Kumhos again, and otherwise on the same suspension (Motons + Vorshlag plates) and running the same power level (430 whp) and aero (our custom mega wing + LS splitter).



The black '13 GT, however, needed much more track prep help - but we only had one day to do it, with the sudden change of schdule on our E46 BMW. While the '13 started out life 45 pounds lighter than the '11, it was much less equipped, and missing the much-loved 14" front Brembo brake package - which also includes wider wheels, and different shocks/bars/springs (we think). We had planned on taking our 2001 BMW E46 330Ci to run at ECR in the TTD class, but our painter needed more time so the car wasn't going to be ready, so we hurriedly put the 2013 GT into some sort of track-ready form.



It was still bone stock, with the craptastic 235/50/18 all seasons, 18x8" wheels, stock non-Brembo brakes, stock pads/brake fluid, and stock base GT suspension (which I think is different than the shocks/bars that come on the Brembo equipped cars). I couldn't bare to run this car this stock, as it would shred the tires and be laughably slow, so we threw some parts at it on the Friday before the event. A set of Vorshlag camber plates took the front camber from 0 to -1.7° (with lowering springs the max negative number is closer to -2.8°), threw the old Eibach front bar from the 2011 on, and slapped on a set of our Vorshlag 18x10" wheels and that old set of 295/35/18 Nitto NT-05s that I ran at the Optima Challenge.



As you can see, switching from the skinny 8" wide wheels and 235mm tires to the 10" wide D-Force wheels and 295mm Nittos actually helped the car lose over 27 pounds of unsprung weight/rotational inertia. That is a huge win, but the +60mm of tire should add more grip, too. The crew here tried to convince me to get a set of track-worthy pads for the '13, but I veto'd the idea, as we are chucking the whole stock brake set-up into the trash very soon and I didn't want to waste $300+ on track-worthy pads for a single event. I said "Hey, they are 13" front brakes, how bad could they be?!" I also blew off flushing out the stock brake fluid with some better Motul RBF600 that we stock and sell. Turns out those were two crucial errors in judgement on my part...

NASA @ ECR, Saturday Oct 6

We loaded up the '11 in the trailer Friday night. JasonM made new number and class graphics for both cars and we applied those at about 6 pm - right as the weather went from 80°F and sunny to COLD and overcast. Uh-oh... the forecast looked bleak but I towed the trailer out to ECR early Saturday morning, with Amy following me in the '13. Had to park in the gravel as the place was packed with NASA racers (something the SCCA club racers are sorely missing - more on that in a minute). The HPDE groups were loaded up, as was the Time Trial group, and three big W2W race groups. Pretty good, considering the crap weather and late event date in the year (over a month after the NASA Nationals).



We quickly unloaded and fueled up the 2011 and got our butts to grid. Amy was the lucky driver of the 2011 on Saturday and she ran in the TTS class against a very well prepped C5 Z06, an S197 Mustang AI car with big aero on Hoosiers, and many other quick TT racers. I was the unlucky schlub in the 2013 GT for the day, woefully under-prepped for TTB class - running against TTB fiend KenO and his Vorshlag/AST sponsored E46 M3; he already owned the previous TTB ECR track record at a 1:59.8, which he reset this past weekend by over a second - and he drives the car to and from the track, with a full interior. Anything sub-2 minute is QUICK at this track, too.



Let me back up a second - before the Saturday TT event even began I heard about a fellow TT competitor that crashed coming out of Turn 4 on Friday's practice event. A little tank slapper off into a 2000 pound hay bale that pretty much totaled the right side of this EVO X. So that's two totaled cars in two weeks from local Time Trial competitors - the Mustang at GTA and this EVO here. That sucks, but this is what can happen when you track a car at 10/10ths (or 11/10ths?) Don't forget the potential consequences, and don't short change your own personal safety. Luckily this driver also walked away unharmed, just lighter in the wallet.

Our Previous Lap Times at ECR

So back in early June I ran a 2:03.9 at the Optima Challenge on the 295mm NT-05 street tires, bitching about tires the entire time. The rears would overheat on the '11 within half a lap and I had to baby the throttle everywhere. That was with all of the same aero and the Moton Club Sports but an aftermarket PHB and the softer 450/175# spring rates. Then when we went back in June 23rd at the Five Star Ford track day I ran the big 315mm Kumho V710s, but otherwise the same suspension and aero, and turned a best lap of 1:58.2. Both June events had ambient temps exceeding 100°F. That 1:58 time in June was actually faster than the old track record for NASA TTS class, which was a 1:58.4, set in 2011. So we had thought all either Amy or I had to do was match or better that time from June and we could set a new track record in our street driven Mustang.

continued below...
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Old 08-16-2013, 04:28 PM   #123
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continued from above



Amy went out in the first session, and in the Texas NASA Region the 1st TT session on Saturday doesn't count for the competition, only for gridding the cars in order of speed for Session 2. Kind of weird, but we all know it. Normally the quickest times happen early in the day, like this first session, due to excessive track temps. But this day was COLD, and it only varied from 47-50°F during both days, so track temp wasn't a problem!
She went out and busted off a 2:01 in her first session, which wasn't bad. Then in the 2nd session (or the first one that counted for competition), with no changes other than driving she popped off a 1:58.8!


Amy's best lap in TT session 2, at a 1:58.8

I was floored. She was leading TTS class over some other TTS drivers in real race cars, but in this overweight full street car. I asked her what she did different and she said "I pushed it a LOT harder!" She got out of the car shaking a little but with the BIGGEST smile I've ever seen. Oh man she was HOOKED on R compounds now. This was by far the fastest I've ever seen her run on a road course, and come to find out it was her very first time racing this car on R-compound tires on a road course (I kinda hogged the car at the previous events where we ran sticky tires). "I want some more..."



After her second session we made some lunch, then she hit the track again in session 3, but she only managed a 1:59 lap. We talked to Mike Patterson at lunch about a ride-along for some pointers for her. Mike is a long time AI racer, NASA race director, and one of the gurus at Moton/AST-USA. They went out in an HPDE3 session right after TT session 3 with Mike riding shotgun, giving her advice.



He knows pony cars and this track very well, and showed her a few places to tweak her line, where to track out farther, and some places to brake a tick later in the high speed braking zones. But overall he was impressed with her smoothness, ability to take advice and alter her driving quickly, and the car's lap times. He also raved at how well our 2011 GT soaked up some of the more notorious bumps at ECR, stating "That's the best handling street car I've ever ridden through turn 8 in at this track!" Gotta give credit to his own shop's custom Moton shocks (with DDP pistons + custom valving), and the new Whiteline S197 suspension bits.



So after this 4th session for her that day she went back to the trailer and we fueled up the 2011 once again. She was ready to try some of the new tricks Mike taught her in TT session 4, and the weather was still chilly but otherwise conditions were unchanged. Her main rival in TTS for the day was in a yellow C5 Z06 Corvette had just busted off a 1:57.5 but she felt she still had some left and was going for it....



During her warm-up lap I saw her arm go up, signaling "pit in", and she came into immediately to the hot pits. I went over to see what was up and she said the rear brakes were making a horrendous noise - and I looked at the rotors, and both were split! It probably happened between her 4th session on track while the car parked down at our trailer, sitting in the cold wind cooling down. We had heard a slight noise going up to grid in TT session 4, so I got out, walked next to the car, and listened... then it went away. Couldn't see anything. But as soon as she braked hard once on her warm-up lap the rotor splits opened up. Just a single half speed lap like this wiped out the nearly new rear Porterfield R4 pads, too.
We quickly put the car in the trailer and bombed back across town to Vorshlag. Ryan met us at the shop with a pair of new rear rotors he picked up at O'Reilys and he swapped those + some used Porterfield R4S pads we typically used for autocrossing/street use, just on the back. The front 14" brake rotors and pads looked fine. We reloaded the car and got some sleep.

How About the 2013 in TTB?

Yea, about that. Well we had nobody there shooting pictures for us all day Saturday, so I don't have any "action pics" in the '13, and with only one video camera we didn't get in in-car vids of the '13 either. That's probably all for the best, as it was pretty terrible on track. I cannot describe in words how awful this car turned and braked. It was rather remarkable. Sure, the 5.0 Coyote V8 made boatloads of power, and the NT-05 tires worked "OK" in these frigid conditions (finally didn't overheat!), but the brakes were atrocious and the handling is best described as "boat like".

ECR is a little bumpy. OK, it is a lot bumpy, but with good shocks on our various track cars (ASTs or Motons) we don't notice the surface humps, heaves and bumps at this track almost at all. This 2013 GT was on the OEM shocks, and I'd swear they were 200,000 mile blown shocks and struts if I hadn't seen the odometer reading 600 miles with my own eyes. The front end was porpoising up and down about a foot all down the back straight. Even the corner workers we talked to at lunch remarked at how bouncy and floaty the car looked. First session best time was only a 2:10, but that session doesn't count for times.



Even with maxed out camber, which did help me from shredding the outside edges of the front tires, this car was a hot mess. Like driving a guided missile - all kinds of power, but with minimal turning and no way to stop. The handling was like this: it would turn in, then keep rolling, then bounce through the corners and flail around, seeing both top and bottom of suspension travel several times per corner. Just awful. The base GTs must have a set of noodle shocks and springs. And we even had an Eibach front bar set at full stiff, to try to fight this massive bodyroll. And big 295mm tires on the thing, up from 235s. It was all "lipstick on a pig" with the stock suspension, though. This car needs better shocks and springs BADLY.

By TT session 2 the base GT's 13.2" front brakes were going away quickly, and by that session I realized the brakes only had ONE hot lap in it at a time, then needed a really slow cool down lap to get the brakes to come back. I was braking the '13 a solid 50 to 100 feet sooner than in the '11 but it was still barely staying on track. And one time, it uh....didn't.

I was coming down the back straight in TT session 2 at what the (second, borrowed) AIM Solo later said was 115 mph. I go to brake for turn 7, down shifting from 5th to 3rd... but there were no brakes. Pumping madly, nothing happening. I could say I was still "getting a feel" for the stock pads and braking system but I was abusing the crap out of the car, to try to make better lap times due to the abysmal handling. It was too much and the front brakes just didn't have anything left. I won't blame the equipment, because I bought the car on purpose without the Brembos, then left the craptasic stock pads and fluid on there, then over-drove it; I have to blame myself for not having the forethought to replace these critical OEM bits + the extra abuse I was laying on the car.

So in TT session 2 on Saturday I went WAY off the end of the back straight, still doing about 80 mph, even though the entry speed is about 50 mph (according to the data I was doing 123 mph and slowing down to 51 mph in the '11 GT - lots of braking). The corner workers had a good laugh at lunch. "We thought that car would never stop!" I was a good 100 yards off in the dirt, but the tall and soft 4x4 stock suspension at least soaked the off-roading up well enough. Only evidence was a little stalk of grass in the grill, and otherwise zero damage. I got off lucky.

continued below
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Old 08-16-2013, 04:29 PM   #124
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continued from above



Turns out the front brake pads were done by the end of TT session 3, as shown above. Went from brand new full depth OEM pads to a hair off the backing plates in three sessions. Half of the pad material seems to be sitting there inside the front wheels, where I parked after coming off track! Since we had no times in TT session 1, and I earned a big fat DSQ for TT session 2, I had to go out and nail down something in TT session 3. Surprisingly, with much attention paid to the quickly fading brakes, I nailed down three laps in the 2:07s with a best of 2:07.33. By then my nerves were as shot as the brakes and I changed my role for the rest of the day to "Amy's support crew". I finished 3rd out of 4 in class, well behind KenO's 1:58.678. Oh well, not very shocking... since the car had no shocks! :P

I am glad I got to experience the nearly bone stock '13 on track, so I can be better informed when I talk about how important suspension upgrades are for this S197 chassis. After running in the beautifully handling '11 GT all day, Amy had zero desire to drive the '13 on track for Sunday, so we drove it back to the shop, following the truck and trailer pulling the '11 in for rear rotor replacement.

NASA @ ECR, Sunday Oct 7



Sunday TT Results: http://www.nasatx.com/resultspoints/..._Sunday_TT.pdf

Sunday we pulled up back at the track and quickly unloaded the '11 GT. I was driving it that day and Amy was support for the day - but secretly she hoped for a session or two in the car. She was still REALLY pumped after tracking it all day Saturday. We put in a little fuel and got to grid in time. The weather was again 47°F and warmed up to a balmy 50, with a little less wind than the day before - but still plenty cold. The schedule showed the same cars entered, with Michael Perkins TTS C5 Z06 the biggest threat, who won Saturday's TTS class with a best lap of 1:57.5. TTA was a good 2 seconds quicker that day, so I was worried that a certain EVO might jump up to TTS to reset the track record in this class - but they weren't listed in TTS (yet).



I went out and pushed hard in Sunday's TT Session 1 and got a best lap of 1:57.354, and was the quickest TT car in the session. Out again in TT Session 2 and ran two nearly identical 1:57.14 laps, only a couple of tenths faster. Mike Perkins took his TTS Z06 to a 1:57.390, so it was close! I didn't know at the time (they didn't get his class right until session 3 results were posted) but Josh Dunn's TTA classed gutted EVO had jumped to TTS for Sunday and was already running a 1:56.471.

For TT Session 3 I pushed a bit harder in a few spots and managed two more 1:57.11's, with one of those watching the AIM having a Forecasted 1:55.8 lap, right until I put two tires off exiting corner 11 onto the front straight. GRR! I knew the car had a high 1:58 in it but I couldn't even break the 1:56s in three sessions, which was very frustrating. It was in this session that Josh Dunn had cinched the TTS class with a 1:55.326, and the results finally showed him in TTS, so I knew I was out of contention for the day. Oh well, I took to TT session 4 with a vengeance, determined to get that 1:56 lap, just to make that personal milestone.


Click the image above to see in-car video of Terry's best lap of 1:56.33

So the two hot laps from TT session 4 in the video above were hectic. I passed 3 cars in traffic to a 1:56.9 lap, then had a semi-clear lap of a 1:56.343, with a car spinning off track in front of me (I lifted a bit there to make sure he wasn't coming back on track). I talked to the driver of the black TTS S197 Mustang, and it is a soon-to-be-AI car but he was running on Hoosiers, makes 400 whp with a 351W, and the car was about 200 pounds lighter than our '11. It looks like I was only catching him under braking, and most of that into turn 7.



By the end of the weekend on Sunday Amy and I were both utterly exhausted, but we both felt really good about our lap times. She wanted one more shot at the car on Sunday but after seeing how close to a 1:56 I was she let me take all 4 sessions. For Sunday I finished 2nd place to the EVO, a full second back, oh well. I beat the old TTS track record by 2 full seconds, so damn the new record! A 1:56.3 is still pretty darned quick for a full weight street car with good suspension, some aero, and two engine bolt-ons, I feel. We have had a lot of racers tell us the same thing in the past week, too. Mark Smith reset the American Iron track record at ECR with a 1:59.848, in a Boss 302-S, for comparison. The best ECR lap I had run prior to this was way back in 2008 in the E36 LS1 Alpha car, with a 1:57.2 in a gutted 2500 pound BMW with the same 315mm R compounds. We discussed our lap times and any ways to improve them in this car over excellent TexMex food from Fuzzy's Taco Shop in Sanger, TX, located at the interstate outside of ECR. This is the perfect post-race meal!

continued below
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Old 08-16-2013, 04:30 PM   #125
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continued from above

Explain The Gains

What made the 2 second improvement in this car since June 23rd? That is a BIG jump in time for a car that is otherwise unchanged, and one that we have driven so much at this track (I am not really "learning to drive the track better", having made many hundreds of laps here in the past five years). The only changes to the 2011 GT since our 1:58 laps were the slight bump in spring rates (which I detailed in my last post) and the addition of the full suite of Whiteline S197 components. I might sound like a broken record but this Whiteline stuff really has transformed the car, which we have noted at the Solo Nationals, GTA at TMS, and at NASA at ECR this past weekend. The Watts Link is the big game changer, but their swaybars, LCAs and rear relocation brackets helped, too. This stuff works, and more importantly, it doesn't make any racket on the street.



I am very, very impressed with the Whiteline parts and apparently you guys are responding to our positive results, with a lot of Whiteline S197 (and BRZ!) sales in the past few weeks. Thanks.... because in the end, that helps us keep doing what we're doing: trying new products, designing our own parts, and racing on them to prove what works and what doesn't.

Dyno Testing

So on Wednesday of this week we took three of Vorshlag's project cars to True Street Motorsports in McKinney for some dyno testing.



Nothing earth shattering here, just a routine "check-up" dyno pull on the 2011 GT and a first "Baseline" pull on the still stock 2013 GT and Matt's 2013 BRZ. Weather kind of sucked, with 100% humidity plus spitting rain, and even with SAE standardized corrections the 2011 tested a tick lower than the 430 whp pull on the same dyno back in Spring, but still pretty close at 424 whp.



The 2013 also made exactly what I thought it would make at 376.9 whp - within 1 hp of the 2011 GT when it was in stock form (378.5 whp). Ford re-rated the Coyote 5.0 in 2012 with an additional 8 hp (412 -> 420) but it didn't show up on our dyno test. Me thinks it was marketing fluff.



Still, 377 whp is nothing to sneeze at, and most of the reason why the 2013 was able to knock down that 2:07.3 lap at ECR. Like I stated above, the only thing it had on track was horsepower, as the brakes and handling were pretty much crap in stock form, in my view. It was a big floaty missile, that once you got it pointed in the right direction would gobble up straight-aways, but sometimes fly off the end of them. We were a solid 4 seconds faster on the exact same set of 295mm street tires with just better suspension/brakes in the '11 GT, and the 47 hp difference between these cars wasn't where we made up 4 seconds. Then we were fully 11 seconds faster with the tweaked '11 GT on slightly wider R compounds. And driving the '11 GT was much easier and confidence inspiring.



The overlay dyno chart above is showing all three cars: the 2011 GT with headers and a cold air (plus a custom tune by True Street), the bone stock 2013 GT, and the bone stock 2013 Subaru BRZ. Look at the shapes of the dyno curves for the stock vs modded 5.0 GTs - they are remarkably similar. The big 1-7/8" Long Tube ARH headers and the Steeda cold air added torque and horsepower EVERYWHERE, with zero loss of torque at any RPM. In fact there is an extra "torque hump" on the '11 at the extreme low end (2500-3200), which is very noticeable street driving both cars back-to-back. For the 2013 GT's headers I am again going with the bigger of the two primary options on the ARH long tubes, as it is simply a win-win over the 1-3/4" primaries (as ARH told me, the 1-7/8" full length units "make more power everywhere" than the smaller primary option).

The little BRZ made 167 whp, which was more than I thought it would. About right for a car rated at 200 hp (meh, so it is about a 16% drivetrain loss). And yes, our 2013 GT stickered ($31K) almost the same as the BRZ ($27K), but the GT was actually purchased for several thousand dollars less (with that $1500 rebate, + it is domestic and therefor they deal). But you don't buy a BRZ or FR-S for horsepower, you get one because it is a nimble RWD chassis that weighs almost 800 pounds less than the solid axle GT. Completely different animal. You can read more about our exploits with the "FT86" chassis in this thread on VoMo forums, also located on NASIOC, 'Carvers, RRAX, and SCCAForums.

What's Next

I swear the 2013 is getting it's own thread very soon. We have been removing parts, weighing things and gathering all sorts of interesting data on this car, so the new thread will have some new information worth reading. Our 2011 GT project thread here will continue, as we plan to keep tracking and street driving the red car.

The next event for the '11 is the Five Star Ford track day on Nov 17th at ECR. Vorshlag will be there with our trailer and some of our race crew to help support the many Mustang drivers likely to attend. We can help check your alignment, help set tire pressures, and will be giving ride-alongs in the red car with me or Amy driving. That should be fun!



The 2011 was back to street duty on Monday after a wheel swap. After we leaned on Wednesday that the SCCA PDX event was cancelled the crew here at Vorshlag swapped back to the stock trunk, too. The 2013 GT is badly in need of a bunch of suspension parts, to rid it of the 4x4 look and parade float handling. The uber-light brakes we will use are another three grand, and there's the LS back seat delete kit that is only another $900 more. Another set of custom Forgestars would be help, then we can get to cutting the fenders to make the big tires fit. I really need about five grand to build or buy what we need to get started. Hopefully my 2001 BMW E46 330 will sell for good money in the next couple of weeks (it just came back from the painter yesterday and looks flawless!) and I can use some of that cash to throw at the 2013.

I am almost done writing our "How To Build your 2011-2013+ Mustang for Track Use" article, too. Our entire crew is helping contribute to that one. We have had customers asking us for "the wish list" so we finally put it down on paper. Err... electronically. In that article we will finally list out which modifications we think help lower your track times the most, and in which order we recommend doing them in, with some budgetary numbers along the way. We also will list out what options to look for when ordering or buying a 2011-13 Mustang as well - "How to Buy a Mustang The Right Way".

More soon,
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Old 08-16-2013, 04:30 PM   #126
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Project Update for Nov 16, 2012: Wow, has it been a month since my last update to this build thread? We've been buried and posting on our other build threads, but I neglected this one. We had an autocross two weeks ago (last one of the year) and have a track event tomorrow that we're loading up for. And the eBay auction on my 2001 BMW 330Ci is still going strong (ends Tuesday Nov 20th at noon!). Anyway - busy busy, so let's get caught up with a quick update.

SCCA Autocross, Crandall, Nov 4, 2012

Two weeks ago we had the last autocross for the year lined up. We had the 315/35/18 Kumho V710s still mounted to the Forgestar 18x11"/18x12" race wheels. Hmm, swap to the Hoosiers for this autocross or not? It was the last event of the year and I had the regional class championship wrapped up, so I blew off the extra work of swapping tires and had the guys here at Vorshlag leave those on the race wheels and the 315/30/18 Hoosier A6s stayed on the tire rack. If it was even remotely warm they would probably do all right, and I doubted Madarash would show up to two SCCA regional events in a row (my main ESP competition in this region - the reigning and 8 time ESP National Champion who is brutally fast every time).



Well, I was wrong... he did show up, but didn't run his car. Opie Viets brought his '84 3rd gen Camaro down from his region and ran with Madarash co-driving. And they ran Street Mod, in an earlier heat. Opie's car was similar to Mark's in many ways, and even had Madarsh's old double-adjustable Konis and some other parts of the set-up were the same. But it wasn't Mark's actual 3rd gen, and he told me this past week that it still needed some work. So yea, "I beat Madarash", technically, but it wasn't a real victory - it wasn't his car, running in the same class or heat. But.... I never get to say that much, so I gotta sneak it in whenever I can!

Strangely I did place 2nd out of 112 in PAX, which was a first for this car. It was frakkin working WELL on those Kumhos!?! So Amy and I drove together in ESP and ran in the last heat of the day. Temperatures were mild all day and there was water on two parts of the course for everyone's runs. It was there in the morning and kept seeping up through some cracks in the concrete pad, so we all had to deal with it. Oh well, could have been in worse spots.



The course was the same as two months ago for the first 1/4, then it had some tight turn-arounds with short acceleration zones coming out, with lots of tight TIGHT transitions. Walking the course I feared losing to street tired Miatas in STR or the narrow slalom buggies in STX, but luckily that didn't happen. Putting 2.5 seconds on STR and 4.5 seconds on STX was unusual for us, but it felt gooood. Even with a lot of tight stuff the big S197 did all right.



Everything seemed to work well that day, for once. The shocks worked brilliantly, as always, but so did the brakes. No "ice mode" or lack of power assist, like the last time we ran here (we put in the 2nd replacement brake booster vacuum hose grommet before the NASA event). The tires were pretty cool all day, but we finally got some heat in them after our 4th runs, which seemed to help. With the new stiffer spring rates we added after the Solo Nationals, and the stiffer swaybar settings that seemed to work best in our private test, the car corners flatter and transitions violently.



A nice surprise was Amy getting interviewed by a camera crew shooting for "Mobil1 The Grid". The interviewer even rode through with Amy and was all smiles after hopping out. They interviewed a half dozen racers so it might not "make the cut", but she put on some good runs and did great on camera, and the car looked and sounded great. She was a tenth off of Madarash's time, and a second quicker than the 3rd place ESP entrant, also a Solo Nationals veteran. The Mustang was just stinkin' FAST that day. So ... we will know if she made the cut when the show airs on Speed (or FoxSports1?) next March, I guess.



An old college buddy and my current engine builder (HKRacing Engines), Erik Koenig, was in town delivering two LS1 engines to Vorshlag, so he stuck around and came to the autocross. We watched some of the event from atop the drag race bleachers then he rode through with me on three of my runs. He taught me most of what I know about autocrossing back from our TAMSCC college racing days, and was the first person I ever rode through with in an autocross run with on race tires - which totally ruined me, and led me to go to college at Texas A&M University in the first place! He used to race well against Madarash in ESP in the early 1990s, so he got to talk to him again after being away from the sport for the past decade. It was good to see him out again and I hope he gets one of his Mustangs back into autocross worthy shape soon. Big shout out to my buddy Ed from Pirtek, who came out to "crew" for Amy's and my runs. When you're driving with two folks in a small heat, with numbers to change, tires to check, shocks to tweak, passengers on every run, and a TV crew shooting video of all of that, this really helps - so thanks!



Above is the in-car video from my fifth and best run. It had a huge mistake in one of the tight 180° turn-arounds, and I blew off the run after that. The right rear started spinning after that flub and I just matted the throttle, pissed off at my mistake, and just drove like an idiot to the finish. And dropped almost 9 tenths?! I am still scratching my head over that one. I guess all of my other runs were worse - and they all did have mistakes. I never claimed to be a good driver, but sometimes I luck into a good run. I didn't hit a cone all day and Amy was also pretty clean with only one cone, and we were stepping on cone bases. She managed 2nd in class and 11th in PAX, also a good placing for her.

continued below
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Old 08-16-2013, 04:31 PM   #127
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continued from above

This was our last autocross planned for the year. We have lots to work on over the winter to this car, mainly turning it into a more track-worthy car, with the compromises of running "autocross and track and street" down to just "track and street only", as the 2013 GT is getting closer to ESP set-up. We have another set of coilovers on hand for the '13 (AST 4200RR), as well as a Watts Link kit (Whiteline, of course), and some other bits and pieces that we will show in that build thread (I will link it from here when I start it).

Preparation for Five Star Ford track day



So that was two weeks ago and today we're prepping the 2011 GT for another track event. This is an informal HPDE put on by the Five Star Ford of Plano dealership where we got our '13 GT, and the dealer we got that car from is setting this up (Corey White). This is the same group that did this back in June. Weather for tomorrow looks nice and we should have 40-50 cars. Amy will be driving the '11 GT and Matt will be in his BRZ (which got 255 Hankook R-S3s on the 17x9" wheels, Carbotech brake pads, and an oil change today, too).



One of the biggest changes to the '11 GT was a height reduction on the rear wing element. After hearing from several aero experts about the poor placement of our APR 3D wing element ("it doesn't work above the roofline!") we finally got around to shortening our custom built wing uprights. Ryan took 5 inches out of the height and the element now sits below the roof line.

Ryan, and our new tech that started this week Olof, got the Mustang and BRZ cleaned up, inspected, tires swapped, brake pads swapped, and the red car is being loaded into the trailer now. We will be out at Eagles Canyon bright and early tomorrow morning to put in some solid laps in both cars.



The differential in the 2011 GT is fried again, so we'll order another carbon clutch pack rebuild kit from Ford and get that installed in the coming weeks. The left rear outer axle seal is weeping a tiny bit of fluid, so that needs to be changed. The next event for this car is another ECR track event December 8th - the annual "Toy Run" event.

2012 Mustang Boss 302-S Prep

During the week of Nov 5-9th we worked on American Iron racer Mark Smith's Boss 302-S race car here at Vorshlag. Figured I'd show this car, as it has some pretty cool parts and capabilities as delivered from Ford. I will show more on this car in a future post, too.



After setting a track record at ECR in October, he brought the car to Vorshlag for some more tweaks, updates, and repairs. We had discussed some weight saving items we could tackle for a good 75+ pound drop in weight. American Iron runs with a power:weight formula, and the 302-S can run a variety of restrictors to go up and down in power. With a lower weight he can run less power, then add ballast to use a larger restrictor for more power at bigger tracks. Flexibility...



The big update we made was a new custom mandrel bent exhaust, to replace the nearly stock parts that these cars come with. We left the stock exhaust manifolds in place, as much as it pained me, and concentrated on a lightweight, high flow race exhaust that included 16 gauge Stainless Steel mandrel bends, two 4" round Magnaflow stainless mufflers, and a custom X-merge, all made in-house here by our fab guru Ryan. The new system stopped just below the rear axle and the car dropped about 45 pounds - and picked up a lot of power.



The entire system is tucked above the bottom of the frame rails and shouldn't ever scrape anywhere, unless it runs over something off track that only hits under the middle of the car. Ryan added heat shielding to the tunnel near the tips, built custom hangers with poly mount bushings, and it looks and sounds amazing.



With the stock air filter/box in place and the stock exhaust manifolds, power jumped from 365 to 420 whp! The old number had a home-brew air restrictor in place, which was changed for a proper restrictor in the throttle body. LG Motorsports dyno'd the car with three different size restrictors and now it has 365 whp again, but a lot more torque than before. He can also run the car at three different weights now and has the dyno charts and restrictors needed for each AI legal set-up.



Ryan built a custom bracket for this sub-3 pound battery Mark wanted to try - and the dang thing works! It charges fast and will start the car at least 5 times in a row with the same charge. Dropped 30 more pounds with this battery, and the old one can be swapped in quickly to add ballast or if the new wiz-bang battery craps out. New front wheel bearings, a strut repair, lots of clean-up work, new fluids in the diff/cool and trans/cooler, and a sound test rounded out our work for the week. Mark was very pleased with the car, the exhaust still managed to only blow 95 dB, and he did well at two races at NOLA last weekend.


Video of the drive-by in the 302-S with a sound meter at 50 feet.

A rear main seal leak (that we warned him about) became worse in those two races at NOLA and a slipping clutch ended his weekend early, after the second race. He managed to secure 2nd overall in AI for the year for NASA Texas, so he was happy with that (he only ran about half of the races). Next year - look out! I suspect Mark's 302-S will likely win even more AI races.

Anyway... this quick post grew a bit! I better sign off and help get the trailer loaded. Until next time!
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Old 08-16-2013, 04:32 PM   #128
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Project Update for Nov 30th, 2012: We had a track event in the Mustang since our last update and Amy set her new personal best lap at ECR. We've also finally modified the 2013 GT with real suspension bits, but that will be covered in that car's own thread. And after a considerable wait we finally have AST 4150s in stock for the S197 Mustang (and Vorshlag bought the entire order)!

Five Star Ford HPDE, ECR, Nov 17th

In our last project thread installment, we were preparing the 2011 GT for a Ford-centric track day at Eagles Canyon, our local 2.5 mile road course that is bumpy, but fun. This is where we do a majority of our testing and where Five Star Ford (a local Ford dealership - and where we bought our 2013 GT) had their first HPDE event back in June. This track is a brake intensive track, as I have mentioned before, and Amy drove the car exclusively all day and took the rear brake pads down to the backing plates. The pads were marginal when we got there and she still managed to get three HARD track sessions in before they started making racket and she brought it in.

Vorshlag Picture/Video gallery: http://vorshlag.smugmug.com/Racing-E...ar-ECR-111712/



Our photo guru Brandon went with us and took some great pictures, and Ed from Pirtek Plano South joined us out there as well. Matt brought his BRZ with our camber plates, some fresh 255/40/17 R-S3 tires and Carbotech brake pads and was tearing it up as well. I came out to watch, ride along and instruct, and to maybe take a few laps in one of our cars. In the picture above, I was riding through with Amy and it looks like I am yelling, but I'm probably saying "Gas! Gas! Gas!", to try to push her to faster lap times.



Ed and I (above right) got Amy's and Matt's cars ready, plus helped a few racers adjust camber or fix some small issues. I rode along with a number of other racers, including Matt in his BRZ, another FR-S driver Stephen F, and Amy in the '11 Mustang. After my ride along with me that day, plus Mike Patterson's in-car instruction from the NASA event in October, and maybe with some help from the new (more effective?) rear wing location, Amy lopped a second off her previous best lap to the tune of a 1:57.7.


Click above for in-car video from Amy's 1:57.7 lap.

This was again a pretty cold day (50s), very similar to the NASA event the month before, and she was pushing her braking zones and using more of the track on both corner entry and exit. She gave ride-alongs to Ed, me, and event organizer and Five Star Ford super dealer Corey White. Everyone had a blast riding along, the spectators loved watching/hearing her car on track, and she had the fastest car on track that day by a good bit. But as one onlooker said, "It ain't got that whistle!"



Vorshlag/AST tester Ken O and another Vorshlag/AST customer Jason had their E46 M3s out there in the Advanced group with Amy, both running Continental road race slicks (made by Hoosier). Ken normally runs 1:57s on Hoosier A6s, but could only get a best of 2:01 on these Conti's. I went out in a session in Matt's BRZ and had a BLAST, getting a 2:10.5 best after getting blocked on one of my few laps (AIM Solo showed a 2:09.5 predictive before that). Matt knocked off a 2:11.0, which was still damned quick especially since he hasn't been on track in about two years! That light, little RWD coupe is fun, with tons of grip and lots of brakes, but just very little power.



At the end of the day, the rear brakes were finally used up and it looked like we had a rear axle seal leaking a little (it melted), so we loaded up the Mustang and headed home. Amy had a grin from ear to ear and couldn't wait to get back out on track! I think we've created a monster - if I could convince her to let us build her a W2W car, I would love to get her out there mixing it up with the AI boys. The next day I unloaded the car at the shop and went to buy a (basket case) '97 M3, for parts, then unloaded that, so it turned into an all around busy weekend.



Repairs from ECR

So at this event the Porterfield front and rear brakes got used up, and then some. We already had a compromised pad set-up on the car, as we wanted to get rid of all of the rest of the Porterfield pads we had on hand, and Amy took care of that. The rears were to the backing plates and the fronts weren't much better off at day's end, but they were worn to begin with. On Monday after the event we swapped on some street pads, turned the rotors, and bled the system.



We have mentioned the Porterfields brake pads in the past, and we have had decent results from them, but when Ryan and the crew have switched from track (R4) to autocross/street (R4S) pads, the pads coming off tend to crumble and fall apart. This has happened to three sets of pads, which each had more than 50% pad life left... we pulled them out of the caliper and the friction material crumbled, fell off the backing plates, and were then junk. This was getting ridiculous and expensive, so we have now switched to another brand. We had even worse luck on Hawk brake pads. Not knocking these brands, just didn't work well on the Mustang.


Carbotech pads going on the '13 BRZ

Before the November 17th ECR event, we ordered some Carbotech pads (XP12 front, XP8 rear compounds) for Matt's BRZ. The pads themselves LOOKED really good - and yes, you can see quality differences in brake pads. After driving the BRZ myself for a session at that event, beating on the brakes relentlessly, and then seeing the lap times and data I logged on this car under braking (1.4g!), I am a believer. The Carbotech pads didn't fall apart or wear the rotors funny either, like the Porterfields have been.

continued below
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Old 08-16-2013, 04:33 PM   #129
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continued from above

I liked Carbotechs so much we have since become a dealer. Now we have ordered their track pads for the 2011 and 2013 Mustangs and we'll see how these do next weekend. XP20 front and XP10 rear for the '11 (race tires, Brembos, ducting) and for the non-Brembo equipped (ugh) '13 we got XP12 front and XP10 rear (street tires, small 13.2" front brakes, stock power). We will see the results soon enough but I've had several American Iron racers tell me Carbotech were the best pads they have ever used. After seeing the results on the BRZ, I believe them.

So the '11 GT's front Brembo calipers have been rebuilt already, as the dust seals had burned and melted mostly away. They lasted almost two years under abusive braking on this FAT ASS car, at a lot of track and autocross events. After the latest ECR event, Ryan noticed the rear dust seals were melted, along with the caliper guide pin dust boots and rear axle seals. The rear calipers and guide pin dust seals have all been replaced and the rear axle seals will be swapped out for new ones next week, when we rebuild the Traction Lok differential once again. We debated going to a better aftermarket differential in the '11, but decided to "punt" on this decision (we won't race again until late January or early February) and instead ordered another $110 FRPP carbon clutch pack replacement kit. The '13 GT will get the better differential first (likely a T2-R), as it is more important for autocross use than on track.

AST 4150 Coilovers for S197 in Stock

After almost a year of waiting, they are here! The 4150 is a new shock model from AST that is a single adjustable monotube coilover strut/shock combination that we have been waiting for since late 2011. I won't bore you with all of the details, but the development and then initial production took longer than expected; the first sets arrived yesterday. I also won't bury you with too much sales talk, as you can see more details about the 4150 at this link.



There I go over the history of the 4100, the changes to the 4150, and explain how Vorshlag helped in our small way to both develop and get these made. It turns out that Vorshlag was the only AST dealer who was patient enough and who believed in this product enough to put in the orders, and we just received all of the 4150s likely to be delivered in 2012. We have a number of S197 and BMW E36 models in stock, ready to ship.



To allow for the maximum amount of travel in the rear of the S197, we had AST make the rear shocks completely different for us than what they normally do. We've tested these rear shocks three different ways and the configuration we went with allows for maximum total stroke and no in-board wheel interference. We keep the (replacement, coilover style) spring in the stock location, use some AST supplied adjustable rear spring height platforms, and machine our own Nylon adapters to make these platforms fit the S197 chassis. We're making these adapters in house now (I made the pair in the above left picture on our lathe yesterday) and supplying them with each 4150 kit at no additional cost. It is highly unlikely that you will see another AST dealer selling AST S197 shocks made to the Vorshlag spec.

Again, you can ready more about them in this link.

Prizes and Kudos

Just found out moments ago that our red 2011 Mustang won 1st Prize ($400) for the Street Prepared category in the "Black Magic Shine Awards" at the 2012 SCCA Tire Rack Solo National Championships. And can you blame them? That Mustang looks GOOD. :P



Also received all of the prizes from the Global Time Attack event at TMS. Ken O picked up my Ducati Limited edition Oakley Sunglasses, which are pretty sweet (below, left).



We also won a $300 Whiteline product credit at GTA for the class win, which I put towards another Watts Link kit for my 2013 Mustang GT. They also made this video (click here or above, right) where they interviewed me at the GTA event, which they showed in their 2012 SEMA booth on a loop. Pretty cool surprise, even if I look like a bog dork on film.


What's Next?

We have another track event December 8th at Eagles Canyon Raceway once again, but this will certainly be our last track event of 2012. We are taking four cars out there this time: the 2011 GT, the 2013 GT (with a full "Stage 1" AST/Whiteline/Vorshlag suspension installed), Matt's 2013 Subaru BRZ and the 1998 Firebird ChumpCar for its maiden track voyage. This is their annual "Toy Run" event, which the owners of ECR hold in December of each year to raise money and get toys and foods for charity. It is also very very affordable for the racers: $50 + a $10 unwrapped toy + 2 canned food items. As you can expect, it brings out a LOT of people, and many of them are new to track events, or are autocrossers. We go to the Toy Run event every year and ALWAYS have a blast, seeing lots of friends that are track junkies and cone punchers alike. If you are in Dallas, come join in the fun!

MORE INFO........
Contact: Maggie Williams
Organization: Eagles Canyon Raceway
Link: www.eaglescanyon.com
e-Mail: [email protected]
Phone: 817-992-9774

We also have been modifying our 2013 Mustang GT with what we are calling our "Stage 1" track setup. This car is now equipped with all of the most important bits we recommend in our "S197 Mustang Handling Guide" (which will be published soon). See details below.



Vorshlag S197 Stage 1 Suspension Set-up: AST monotube adjustable coilover dampers, stiffer rate coilover springs and a lower ride height; Vorshlag camber/caster plates and upper spring perches; Whiteline Watts Link kit; adjustable front sway bar; Vorshlag/D-Force lightweight 18x10" wheels mounted with 295/35/18 Nitto NT05 tires; Carbotech brake pads. All told this is about $6000 in parts, but it makes a HUGE difference in on-track performance. Ideally this car would have the 14" front Brembos but we are eventually turning this into an autocross-only car, so the big brakes were skipped on purpose. Anyone tracking an S197 would be FOOLISH to not get the 14" Brembos.

This set-up is 100% street friendly, with a great ride that should even get the "wife approved" status. Notice - we have made NO power mods to this Mustang at this stage. The 5.0L equipped S197s already makes 380 whp bone stock, so adding more power should not be in your first round of modifications to these cars. It will only make the car harder to drive until you step-up to larger R compound rubber. Ask me how I know this. Of course nobody listens to that, and modifies for more power first... Oiy!

We will run my black 2013 GT equipped as shown above next weekend at ECR. With a data logger and on-board video we will see how much improvement (if any) we have made over the "baseline" set-up we ran in October (which was these wheels/tires + camber plates only, with a best of 2:07 laps). The Vorshlag crew is also going to be driving Cadillac CTS-Vs at COTA on December 7th - the new Formula 1 track in Austin - the day before the ECR event. Should be another fun weekend!

More soon,
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Old 08-16-2013, 04:34 PM   #130
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Originally Posted by GT Muscle View Post
I've been reading this build for few days now, with some skimming and skipping I finally finished.

There are several weight reduction I haven't seen you try yet, BMR's K-member and arms(31 lbs), MMR tranny CF tunnel (they claim 75+ lbs), MMR CF trunk (25lbs), and if you're going hardcore, JPC offer ligher axles and final drive.
Wow, those are some pretty extreme weight saving mods. Let me address them each in order:
  • The K-member is not allowed in almost any SCCA racing class so we didn't look at this. I have installed tubular K-members on several Mustangs and they are not a perfect, no-compromise mod. The suspension geometry is often altered in these, and if the unit is built for weight savings (drag racing) it can even have more deflection under load than the stock steel piece. The road race versions are often only 10-20 pounds lighter, which isn't much considering their price, complexity, and time to install.
  • A CF trunk is also a costly one, and wouldn't work at all with any sort of wing mounted to it like we run on track. You would then need to brace the wing all the way down to the frame, adding structure and weight along the way. And CF trunk wasn't legal for the racing class we used to run in this car (SCCA ESP) so we couldn't do it. Now we could, but it is a costly mod for the weight lost.
  • CF Tunnel? What the.... you mean they cut out the stamped steel unibody floor and bolt or bond some CF replacement in there??? That sounds like a nightmare on many levels. First, you would lose all sorts of structural rigidity. I suspect this is for fully caged race cars only. That isn't at all what we have.
  • Lighter axles would probably mean weaker, too. Sure, you can probably get a gun drilled axle as strong as stock, but at what cost?

Originally Posted by GT Muscle View Post
Few Questions:
-Have you done the rear seats yet?
-Since we can fit a 315mm tire on the 18x10 is there a need for an 11"? I see you didn't like the 345 because that was my plan.
Yes, the rear seat is under 28 pounds.



Seat belt hardware is also around 8 for a total weight loss potential of 35 pounds. But removing the rear seat adds a TREMENDOUS amount of rear axle and road noise. It kind of sucks on a street driven car. Have been driving my 2013 GT like this for 2 months and it sucks.



And mounting a tire to a narrower than optimal wheel is "possible", it isn't great for performance. Squeezed tires don't sit square on a narrow wheel, and the actual tread section gets cupped up on the ends, effectively making the tire narrower in use than it really is. The 315mm tire mounted to the 18x11" wheel (front) is even a bit squeezed compared to when it is mounted on the 18x12" wheel (rear).

Cheers,
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Old 08-16-2013, 04:34 PM   #131
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Quick Update for Jan 18, 2013: I've been waiting for something to be published before I posted again, so I'll hold off on a big thread update for maybe another week or two. A lot has been going on in the background.



NASA Time Trial classes had a bit of a shake-up for 2013 but it was only minor tweaks and things worked out in our favor, for a change. We've gone from TTS (now called TT2) essentially down one class to TTA (now TT3), and we can run now run this car at the limit of the power to weight ratio. No more "well, it was overweight/underpowered", it is maxed out. Apparently this new mix-up has made TT3 the most popular class, at least for this first NASA Texas event. We have 9 cars signed up in the TT3 class, so far.



We're loading up the trailer right now to take the red 2011 Mustang down to the NASA Texas event at MSR-Houston later today for races on Saturday and Sunday. Amy and I are splitting up the driving duties over both days. Will post a much more detailed pre-/post-race report when we get back. Well, then I'm flying to New Orleans for a couple days to drive on some new BFGoodrich tires, so it might be late next week or the following. Hoping to get some good intel on this new "Rival" street tire they are making (for autocrossers and track guys that need a 200+ treadwear tire) as well as bend the ear of tire engineers about the R1 and R1-S race tires.

More soon,
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Old 08-16-2013, 04:35 PM   #132
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Project Update for January 29, 2013 : We have a lot of ground to cover on the S197 Mustang thread. so look for several updates over the next week or two. Our last real S197 thread update was in November, and a LOT has happened behind the scenes since then - with respect to future competition in our 2011 and 2013 GT's in SCCA Solo ESP for 2013, plus several track events. We will also cover the new NASA TT3 classing and our first 2013 competition (with a track record + double-win), a track event in December with both of our S197s, the whole Watts Link/SCCA debacle, a new shock/spring set-up we've been testing on S197s, and then the BFGoodrich Rival tire launch event that I attended, where I got to test with four different types of cars and seven types of tires at the NOLA Motorsport park, including FR500S Mustangs (former Miller Cup cars). This set of updates will be broken up into multiple thread posts over the next several days, otherwise it will be too long and I won't get any sleep - and I've been on the road, racing various cars for four of the last five days, then sick with a stomach bug, so I'm beat. Let's back up and start with the preparation on the 2013 GT before the December track event first...

2013 GT Coilover Shock Install

The last time we took the 2013 Mustang to ECR, it was on the OEM shocks and springs and the handling was "frightening", to say the least. The car was hopping and flopping around, like a fish out of water. Lots of lean, roll, dive, and all that bad stuff we are used to on OEM sprung/damped S197s. Our long term plans at the time still included SCCA E-Street Prepared class preparations, but we would still do a track event or two before we got too far down the rabbit hole of autocross-only modifications.



Obviously a big improvement we could tackle that worked for both autocross and track use was to add our normal monotube adjustable coilover upgrade. Since Vorshlag sells AST and Moton monotubes, plus some others, we had several options that would work. We picked up some AST double adjustable coilovers with remote reservoirs for an S197 (AST 4200-RR), a custom test set made by AST-USA for a former employee. These were built with racing style "eye-to-eye" rear shocks, just like the Motons on our 2011 GT. On this car, however, I wanted to keep them "pin" style on top, to allow for the rebound knob to be located in the trunk for easy rebound changes (see above, left). An eye-to-eye shock tends to have the rebound knob located under the trunk floor and, like in the case of our Moton CS shocks on the 2011 GT, we have to remove a rear wheel to adjust rebound. It is a hassle, and that adjustment almost never gets tweaked. so we end up using the same setting for street and track use (which is a shame). So we asked AST-USA to re-work the rear shock shafts to have a traditional top pin and used it with the OEM style shock mount. They swapped out the shafts and adjusters to our favored eye lower/pin upper style and now the rebound knob is easy to access.



Once these were built to our liking, Vorshlag fabricator Ryan fashioned some reservoir mounts for the rear shocks, and cut holes in the trunk floor "spare tire well" to route the reservoirs through without disconnecting the hoses (which is a PITA) - just like on the 2011 GT. I asked him to tweak the angle of the reservoirs to be able to see the knobs easier from behind, which he did. The reservoirs were mounted into the spare tire well using the 2-piece "Seals-It" brand grommets to make this hole water tight. He mocked-up the seals with temporary Clecos, then used small machine bolts and nuts to hold them in place. If the shocks need to be removed from the car, the 2-piece grommets can be unbolted then the reservoir can slide right through the now open hole... no mess, no fuss. The other mounting/routing option for shock reservoir hoses is to drill much smaller holes/grommets and add (very costly) quick-disconnects on each shock line. Even then you still have to bleed off the Nitrogen charge before disconnecting the hoses, and re-fill the N2 when reinstalling. We feel this "big hole/2-piece grommet" arrangement is easier to deal with in the long run, and it is less expensive - but there are a dozen ways to skin this cat.



The front struts were not that unusual, being a typical non-inverted 22mm shaft monotube with rebound knobs on the strut shaft top and the compression knobs on the remote reservoirs (just like the rears). The hoses were long enough to route underneath the inner fender structure and mount the reservoirs just about anywhere in the engine bay. Ryan made some additional reservoir brackets for the front struts, but unlike our 2011 GT this car still had the factory airbox in place (everything is still bone stock under hood, for the lower 380 whp output). This meant we couldn't mount the reservoirs in the same place as on the '11 (which was blocked on this car by the giant OEM airbox), so we thought about it and placed them vertically in the airstream behind the headlights.



Shock reservoirs need to shed heat when they are working (they turn motion into heat), so we always try to keep them cool. Mounting them so that they get cool air from the front end seemed like the best idea. This location doesn't "show them off" as well as elsewhere, but so be it. I've seen some racers place remote shock reservoirs near the worst sources of under hood heat - like above a turbocharger (I've even done this myself) - but you really have to think about where you mount these things to keep them cool. A boiling hot reservoir will not allow the shock to perform nearly as well as one that stays closer to ambient temperature.



As you can see in the "Before and After" shots above, the ride height on the 2013 GT is significantly lowered, with the front dropping 1.25" and the rear dropping nearly 1.75". This gets ride of the huge front-down rake these cars come with and lowers the CG significantly. The spring rates we used were somewhat mild, with 450#/in in front and 225 #/in in the rear. This makes for a very decent ride on the street, but still a sizable bump in spring rates over stock, for better track handling (well, at least the front rates). See the updated spring charts below for the base 2013 GT OEM springs, the 2011 "Brembo GT" OEM springs, and the '07-08 Shelby GT spring rates (equipped with the FRPP M-5300-P springs).



Click the charts above for larger image... LEFT: 2013 Base GT. CENTER: 2011 "Brembo" GT. RIGHT: M-5300-P/'07-08 Shelby GT.

Since I first posted several OEM S197 Mustang spring rate tests, we noted two problems: first, we weren't compressing the springs nearly far enough. We were barely getting them compressed enough to even approach static ride height. So we upgraded our digital spring rater to a new "ram" to allow for 15" of spring compression vs the 4.5" it came with, which let us test over a wider range. These newly tested Mustang spring rates then become much more linear as we tested them over a wider displacement range. Second there was an error in our calculations for "rate at compressed height" that has also been fixed in our default spreadsheet. The measured force numbers never changed, just how we were showing them (rate of rate change vs rate at position). Sorry for the confusion.

So as you can see, we've upped the front spring rate considerably more than the rear on this car once again, which we have found - from a lot of coilover testing - works better with an S197, both on track and on the street. The bigger rate increase up front cuts down on brake dive, body roll and camber loss under cornering forces. It also reduces understeer caused by bottoming out of the front suspension. This 450#/in spring also makes the car transition much faster than with the ~100 #/in rates. Luckily the adjustable AST monotubes do a fine job of managing the 4.5 times increase in front rate. You won't see OEM-lowering springs in this spring rate range because the typical shocks these are used on (OEM style) cannot deal with those spring rates.

continued below
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Old 08-16-2013, 04:36 PM   #133
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continued from above

ECR Toy Run - Dec 8th, 2012

People sometimes wonder why we are based in Texas... "Your summers are so hot!", they say. And while we DO have 2-3 months of a little heat (okay, a lot of heat), we have 12 months of racing every year. This allows us to race and test every month, and we don't have an "off season" huddled away from the cold with nothing to drive. Sure, we had a couple of snow days around the holidays, but nothing that prevented us from missing a track day or autocross.



Vorshlag picture gallery for ECR Toy Run - http://vorshlag.smugmug.com/Racing-E...un-ECR-120812/

So, we were racing in December and back on track again a few weeks later in January, like we do every year. I wrote about the December 8th ECR "Toy Run" event twice already: in part three of my December 28th post in the BRZ Project Thread and in my December 20th update on our Firebird ChumpCar project thread - some of which I have re-inserted here. All of us at Vorshlag had gone down to Austin and driven Cadillac CTS-Vs all day the previous day (Friday) at the new Circuit of the Americas F1 track. That event was a TOTAL BLAST, but when we finished we bombed back up to Dallas, grabbed the Vorshlag race trailer, grabbed McCall's truck and trailer to tow the ChumpCar, and drove two more cars to Eagles Canon Raceway before dawn for Saturday's annual "Toy Run" open track event. We got there and stacked our trucks, trailers and cars in a big clump and set up shop.



With four cars on hand we were a little busy - luckily we had Pirtek Ed there to help "crew chief" all of us (shown above talking to me in the black '13). He wrangled the five drivers and four cars and kept us all going all day, so... thanks Ed! Matt brought his BRZ, we brought the 2011 Mustang and Amy drove it all day, and I drove our 2013 GT on the new AST 4200-RR coilovers. Two of my racing buddies (McCall and Magyar) and I are also building a ChumpCar using a V6 4th gen Firebird and we ran it for the first time that day. Since this was a charity event, they asked the instructors to take passengers for ride-alongs at $5 a pop, and for $10 donated we would ride-along with anyone and "instruct". Between me and about 7 other instructors we raised an extra $600 that was given to a local food shelter, and we gave some kick ass rides to people in some quick-ass cars. I lost count of how many times I went out on track in the '13 and the ChumpCar, or in other people's cars (I drove a GT500 Mustang at one point), but it was a LONG and busy day. Too much fun!


Our 1998 Firebird V6 has been dubbed "F-Turd"... luckily it ran great.

The ambient temps were much colder than the November lapping day and Amy's and some others' lap times were a solid 1-1.5 seconds off their times at the Ford event, when the weather was a bit more favorable. Still, our black 2013 GT, which we base-lined in November, was a solid FOUR SECONDS faster with nothing changed other than the coilover shocks & springs (which were still pretty damned soft at 450F/225R). The same Vorshlag camber plates, same D-Force 18x10" wheels and 295mm Nitto NT-05 street tires, and same bloke behind the wheel (me). I have taken many hundreds of laps at this track since 2008 and wasn't "learning the line", but instead felt like I was wringing every millisecond out of this car. We went from a 2:07.7 to a 2:03.3. A keen observer will note that this 2013 GT, with no aero, bone stock power and the exact same set of wheels/tires, was faster than our 2011 GT was in June at the Optima Challenge event. A lot of that is probably the difference in temperature, but a lot of it was the fact that the car was easier to drive with less power. These Coyote 5.0 engines have plenty of go in stock form, so we would suggest upgrading the suspension, tires, wheels and brakes long before you start throwing more power at your track Mustang. Nobody listens to that, of course.

continued below
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Old 08-16-2013, 04:36 PM   #134
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continued from above



This was a pretty good suspension test, in my opinion. We know this track well and we ran this same car with the same set-up minus the shocks/springs a month earlier. Not only did we drop four seconds on a two minute lap, but we took the car from a bucking, portly pig that was rolling and brake diving and porpoising around this somewhat bumpy track and turned it into a calm, flat cornering car that was nothing like the OEM suspension'd Mustang any longer. I cannot repeat this enough: a bump in spring rate along with proper monotube adjustable coilovers will completely TRANSFORM these cars. The shocks that Ford installs are equivalent to $50/corner Autozone specials. Even the "adjustable" shocks that come on the Boss 302 LS are not good at all - Tokico adjustables are only a small step above the Autozone fare that comes on the GT's. The longer you run on track the more the performance in twin tube shock degrades in handling, as well.


Of course I couldn't resist a little hooning for the cameras... with the stock 380 whp, it's just too easy!

It isn't so much about how many adjustments the shocks have, or the reservoirs, but the type of damper being used. Monotubes are technically superior to twin tubes in every performance measurement, and their MUCH larger pistons can react to bumps much more rapidly and effectively. They tend to have more of an adjustment range and can deal with a wider spectrum of spring rates. We didn't make this a gut busting, over-sprung race car set-up (450F/225R), but instead mildly improved the front rates and kept the rear rates nearly stock. At the same time we lowered the car 1.25" or more at each corner, for a flatter "stance" and a lower Center of Gravity - which directly improves cornering grip. The lower ride height added negative camber, as it always does on McPherson strut cars, and this also helped improve front grip and lower front tire wear.


Andy Hollis giving the point-by from his OLOA race prepped CRX to Amy's '11 Mustang GT.

Amy had fun in the red Mustang and ran a bunch of 1:58 laps, sometimes with a string of 3 or 4 in a row within two tenths. Just couldn't get back down to the 1:57's she ran at the ECR event in November. These old Hoosier tires are just dead, and have "compounded out". We used and abused these for GTA, lots of autocrossing, and multiple track days. They still have tread left, and the wear is perfectly flat across the tread, but they are just getting ... slower. And we still used these same tires at the NASA event at MSR-Houston in January. Just like most folks, we have a fixed racing budget that isn't unlimited, so sometimes we gotta win some tires to get new ones. The rest of the car was flawless and the Carbotech brakes were phenomenal once again. The twice-rebuilt TractionLok differential is utterly gone but again, we need the budget to recover before dropping $700+ on a Torsen T2-R. Meh, we can deal with some imperfection - this is a stick axle pony car after all.



Matt had an uneventful, but fun day in the BRZ. We luckily didn't have anything explode, fall off or catch on fire in the ChumpCar Firebird. It was a big hot mess, and we uncovered some new issues in this fiurst track outing, but we made it through five sessions and three drivers and still drove it onto the trailer for the ride home. The 2013 GT suspension test was great and the 2011 GT was flawless all day. Overall, this ECR Toy Run event was a lot of fun and a very informative test. I have to thank the ECR track owners for putting this much-discounted event on for the 5th year in a row, and thanks also to Brad Flak for corralling the drivers and instructors. As usual, the Toy Run's ultra-low price tag attracted many first time track enthusiasts, including many local autocrossers. Hopefully this exposure to road course driving gets them a little more hooked on doing HPDE events. This worked in the past for myself and many other fellow (and many former-) SCCA autocrossers, like Vorshlag tester KenO - who was a blur around the track all day (above right and below left).



Another Vorshlag tester, and BMWCCA LSR president MarkW, was also on hand in his 1M (above, right), pushing his Vorshlag 1M camber plates and finally wearing front tires flat instead of chunking the shoulders. You 1M owners can thank Mark for the Vorshlag 1M camber plates. His constant stream of camera phone pics showing torn up front tire edges spurred the production of the OEM perches that make this fitment possible.

D-Force 18x10" S197 Wheel In Stock

Back by popular demand is the 5x114.3 bolt circle 18x10" D-Force Racing lightweight wheel. This ET43 offset wheel fits both the S197 Mustang and GR chassis Subaru STI without spacers. There are dozens of sets in stock in both Silver and Flat Black colors. These may not last too long, like last time, and will probably sell out before the next batch arrives. If you want a set, you can of course order them through Vorshlag. Thanks!



That's all we have on this December ECR event and the prep leading up to it, but I have a lot more writing to do to get caught up on this S197 thread. We have several more posts for this thread coming soon, so stay tuned for more.
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Old 08-16-2013, 04:37 PM   #135
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Project Update for February 2, 2013: This thread update covers the first 2013 NASA Texas race weekend we attended in the red Vorshlag 2011 Mustang GT. This January event is always held down south of Houston, but is sometimes plagued by poor weather (rain or cold). I was going to skip this event, but peer pressure worked and pushed both me and Amy to attend. I'm glad we did - the weather turned out to be extremely nice and we had a total BLAST running the red 2011 GT in the new TT3 class.

I will back up a bit and talk in more detail about the classing tweaks that NASA made for 2013, which I hinted at in an earlier post in this thread. This is the first significant classing change that I have noticed in TT since we started running this series in 2008. It looks bigger than it really is, as most of the changes were mostly to the class letters/nomenclature, but there were some substantial changes to TTA (now TT3).


2013 NASA TT Class Updates - Letter vs Number Classes

None of what is written below is official or approved by NASA, just our overview and interpretation of their rules. Don't take our word for it - read the rules yourself if you want to learn how to class your car for NASA TT. These rules only span 54 pages and only parts of that will even apply to a given entry. If you get mired up in the classing though, don't worry - we're here to help. Matt and I at Vorshlag have helped class hundreds of new folks into NASA TT. We have our own "class configurator" that is normally more up-to-date than the one's NASA makes. Shoot us an e-mail and we can help get your car classed, free of charge: info (at) vorshlag (dot) com, with a subject of "Help with NASA TT Classing". We can help with SCCA Solo classing as well, but that might involve substantially more tortured logic.

2013 NASA Time Trial Rules: http://www.nasaproracing.com/rules/time_trial_rules.pdf

NASA classes each Time Trial car into a "base class" and gives it a "base race weight with driver". Each base class has a "base tire width". Some cars have handicap points in their base class, denoted by one or two "stars". One star = +7 penalty points and two stars = +14 penalty points. Then modifications each cost "points", and you get 19 points to play with before you bump up a class. Running below your base race weight costs points (but heavier gains you points back). Running more tire width than your base size costs you points (but narrower gains you points back). The points for parts eats up most of your allotment, but whatever you change you can never violate the power-to-weight limit for a class. It sounds confusing, and it kind of is... but only because it is so unconventional. But this type of classing is also liberating, fun to explore, and competitors can "bench race" set-ups with different mods to play with their 19 points in class. Or you can go buck-wild and use more than 19 points and bump up a class... then you get a total of 39 points (or more) to play with. Make sense? You can keep adding mods or lowering weight or adding power to keep your car at the competitive limit for each up-class jump you make. This is how the new "letter" classes work (TTB-TTF)


Vorshlag built entries for NASA TTD and TTA classes.

Our Intro to NASA Time Trial article, circa 2008: http://www.vorshlag.com/tech_timetrials.php

This means you can have a Miata with wild aero, sticky Hoosiers, and a supercharger racing against a nearly stock E46 M3. And oddly enough, it works, as there is always the power-to-weight element... measured horsepower and measured weight reign everyone in. There are not "categories" to jump up, and anything can eventually be classed with almost anything else, if a given car gets modified radically enough.



In 2012, beyond TTA were the top three classes which were always strictly power to weight based, with no more points to play with. I now call these the "number classes", but in 2012 they were TTS, TTU, and TTR. There are "modifiers" you can exploit, to get you a little more power or a little less weight, if you have say... a 4 door vs a 2 door, or use a 275mm or narrower tire, etc. Otherwise it is strictly power to weight based. When we first started racing our 2011 Mustang in TT (see above), it was in TTB, but since it came with the Brembo brakes (+2), no decklid spoiler (+4), and the CS front lip (+3), we had very few points left to use. If we had added R compound tires and any exhaust mods the car would be easily into TTA and then even into TTS on points alone, due to the SCCA class allowances and rules we were focusing on (STX then ESP). We ran a few TT events with our STX set-up and it was difficult to manage the the narrow-ish street tires (just like it was in autocross!), but our ESP set-up with 315mm Hoosiers or Kuhmo race tires worked pretty well, but bumped us clear up into TTS. We almost won the November ECR TTS class, until a TTU car bumped down their power and ran quicker and beat us. Oh well, we were still too heavy and/or underpowered for TTS, nowhere near the power to weight limit. It was what it was... we were building our car around SCCA rules and letting the TT classing fall where it may. Other than adding the transponder, a brake pad and rear aero change, our Mustang was still set-up around ESP autocross rules for most of the 2012, even when run at NASA events.



Let's look at the old vs new classes in NASA TT, of which there are still 9 classes total. Nine classes, not 427 classes, like in SCCA Solo. Just sayin'. Anyway, most classes had little to no change other than a more clear naming style (numbered classes are power to weight only, letter classes are still points based). Here are the changes from 2012 to 2013, mostly affecting just one class...

NASA TT Classing - Name and Ratio Changes
2012 ... 2013
TTR -> TTU (Unlimited Wt/Hp)
TTU -> TT1 (5.50:1 Wt/Hp)
TTS -> TT2 (Was 8.70:1 Wt/Hp but went to 8.00:1 Wt/Hp)
TTA -> TT3 (Was 8.70:1 Wt/Hp but went to 9.00:1 Wt/Hp) For TT3 only, non-OEM Aero is a 0.5 modifier (in effect requiring 9.50:1 Wt/Hp).
TTB - 10.25:1 Wt/Hp
TTC - 12.00:1 Wt/Hp
TTD - 14.25:1 Wt/Hp
TTE - 16.50:1 Wt/Hp
TTF - 19.50:1 Wt/Hp

As you can see, before there was some overlap with TTS and TTA both having the same 8.7:1 power to weight ratio. But TTA - TTF were still all "points" based as well as power to weight, whereas TTS was only power to weight. Modifications in TTS were relatively unlimited, with those modifiers for certain limitations. So in reality TTS and TTA had very similar on-track performance. Now with the new TT2 and TT3 ratios and the removal of points based modifiers, they have effectively made the difference between TT2 and TT3 more significant and it creates more places to run your car, and more time difference between the two classes.

In order to keep it interesting in TT3, they also let you choose between a 9:1 and a 9.5:1 ratio. If you keep "stock aerodynamics" you can go with the more attractive 9:1 ratio, but if you want wings, splitters or other aero changes you get the 9.5:1. Still lots of room to tweak and play ... and bench race. And since we are in TT3 now, we get to strategize and play with more aero vs more power. Kind of looking forward to testing this.



As you saw in my last "mini-post", we went with TT3 and we chose the 9.5:1 ratio with alternate aero. Hard to give up the big rear wing and front splitter after you've tried it. We had to add a few pounds, but with our most recent dyno of 424 whp, and the +.6 modifier for running over 3750 pounds with driver, we were able to get a race weight of 3775 lbs, with driver. Here's the math.

3775 lbs / 424 whp = 8.903 pounds per hp... +.6 modifier (for running over 3750 lbs) = 9.503:1

continued below
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