continued from above
That lap # 4 in the video above was a 1:56 lap, after which I noted yet another AdvanceTrac fault and came in to reset it and check for more diff oil spewage on the rear tires. A sub-2 min lap was more in-line with what the car should do but still off the pace a bit. For example, KenO ran a 1:55.8 in a TTB car and Allan Page was right behind him, so of course I should have driven faster. David Armstrong managed a 1:53 in a TTS car, so I was still 3 seconds off the TTS pace (which is an eternity). Yes, there are several driving mistakes I made on that lap - but with this being about my 8th lap on this track in 4 years, with an all new aero package and all new grip levels, I wasn't too worried. Excuses... I gots em!
Since that session was cut short, I came in and re-checked the diff leakage - and it was once again wet with fresh diff fluid on the undercarriage and on the RR tire. Crap! I jacked it up, mopped up the mess again, then went out with my student once more. There were several after-session HPDE meetings and instructor/TT meetings and I talked to like 50 people I hadn't seen in forever, so it was a busy day. I wanted to show my student some changes to her driving line, so I took her out for a couple of 8/10ths laps in session 3 (taking a passenger is allowed in TT but it DSQs your times in that session, as does an "off" if you are solo) and we made it two laps before seeing more faults. With the student I ran a 1:59 lap and was hardly pushing it at all - I was working on my braking and line into and through T1 (which is tricky coming off the banking at 140-150 mph) and my apex kept getting
closer to where it should have been into T4 and the T7-T9 complex... With more laps under my belt, I quickly realized where I was butchering all sorts of corners earlier. It just took a while to come back to me.
Right: Mike's AI car was putting down 1:55 laps and he walked away from both Saturday AI/CMC races
Most of the TT guys went slower in Sessions 3 (and did again in 4), as the ambient temps climbed up to 90°F, so I wasn't going to find a stellar lap in session 4. By then I was also tired of the continuous computer faults and worried about more oil hitting the back tire (although I didn't see a
drop under the car after session 3 - I guess it burned/burped off enough excess), so I let the car cool off, and talked to Amy. I was doing good to not have put a tire in the dirt in the 3 truncated sessions so far, given the oil on the rear tire, so I counted my lucky stars and we called it a day. We had a 4 hour tow back to north Dallas ahead of us and Amy was already bored after taking 200 pics, but
not racing in TT herself. We packed up after my student was done (and checked out for solo in HPDE2) and hit the road right as the TT group was going out for their 4th and final session of the day.
Overall it this day at the track was a LOT of fun, and we learned a good bit about the new set-up (its faster than
me on this track!). I had forgotten how much more stressful it is to run on the big banked turns at 140+ mph compared to the tighter, more technical, and slower road courses we run elsewhere in Texas - such as ECR, MSR-C, MSR-H, Harris Hill, TMS infield, and GrandSport Speedway. Still, we have VIR in July to contend with so I need to bring my game up at higher speed events pretty darned quick!
How Were the Upgrades?
As I stated in yesterday's update, the extra front brake cooling
really worked. The brake ducts we added + the Porterfield R4 track pads Costas and others suggested (thanks!) were spot on. I only caught myself giving it a bit more brake pedal on one lap (lap 4 in session 2 - I'm talking to the damn video camera about it! I don't even know I'm doing this), after a mad dash into T1 at high speed (braking from 140+ to around 70-80). The rebuilt TractionLok just flat worked, even through the tighter/twisty turns like T3 & T4, T7-9, and the other tight turns before the front straight (T11-15). Even so, this car is still getting a better diff before the next big autocross (Spring Nationals) to deal with the tighter turns we see in autocrossing.
Looking at the front camber it seems... barely enough (-3.8°). Gonna add more soon
I never felt the urge to adjust the rear wing angle of attack. We had it trimmed out at the lowest setting and it felt... very balanced. According to the CFD data it can generate 600 pounds at the highest AOA, but we had it trimmed down to much lower settings and it felt fine. This was hardly a proper aero test with barely a dozen hot laps run all day, so I will play with this the next time I have more track time. I really want to get a flat "2D" wing on there before we do any real aero test work though. For now... the wing seems to work, and other than the oil on the rear tires, the car worked fine (like in session 3 when it stopped puking on the rear tire). We had bumped up rear spring rate from 175# to 200# (that's the only stiffer spring we had on hand in this diameter and length).
What should the car have run? Well a 1:53 would have been more in line what several people feel the car was capable of - with a better driver. I tend to agree with them, and I know I was way off the pace for what the car should have been doing. If we had run Sunday and found some cahones ... maybe. I need more seat time at TWS to reach this car's potential, for sure. Put me at a track that I know better and I can get closer to the potential, I think.
Other Updates & Upcoming Events
I just talked to the folks at APR and there is indeed going to be a straight horizontal "2D" carbon fiber airfoil in 61", 67", and 70" widths, with an optional dual element 2D style wing. The pricing will be "more competitive" than the 3D wing (its probably easier to make) and these should be out sometime this year. I told them I want a 70" wide unit and that's what we'll perfect our wing design to use. Until then we'll keep this 3D wing on there with the current uprights for track events, goofy as it looks.
There are several events in May that we plan on taking the Mustang. Going to run the NASA TT event May 19th at Grandsport Speedway, located way south of Houston. This is an unusual "HPDE and TT only" NASA event, which makes sense on this smallish track. This will be the first time NASA has ever run there, so all TT class winners will set new track records. Hopefully I can find a little bit more speed (in the car and in myself!) and tighten the gap to the top TTS finishers. This is a tight little 1.3 mi track that I have run before (more recently than 20 years ago) so power and slippery aerodynamics (ie: Corvettes) won't be as big of a factor as it was at TWS. On May 20th there is another Texas Region SCCA autocross at TMS I'm going to attend, so that makes for a busy double-header weekend with a few hundred miles of towing in between. I plan to run both of those events on the Kumhos, so at least it won't take much prep changes between Saturday and Sunday.
Memorial Day weekend has a massive "Spring Nationals" SCCA Solo double-header weekend in Lincoln, NE. Friday and Saturday is the ProSolo while Sunday and Monday is a National Tour. The ESP class is already chock full of good entrants. We have to go to this one to see where we are, and we need to be on fresh Hoosier A6's by then, hopefully with some extra power
and a real diff.
We have to have the updated programming for the steering rack before any of these events, as I'm tired of seeing the same nagging computer errors and steering wheel feedback. Now that we're confident this programming is SCCA legal I'm going to get it done. We will be pulling the rack out of the car this week to send it to Ford Racing, as the replacement $1000+ 2011 GT racks is on national back-order. Apparently there's a 3-4 month build date window where all of the early 2011 GTs are having similar "issues". Ford is not doing a recall yet, but probably will "eventually". If you are seeing this type of steering shudder CALL YOUR FORD DEALER and demand a recall/TSB. If you don't want to wait, call Ford Racing in Detroit. All of the World Challenge and GRAND AM Mustang's run this update programming, and it supposedly fixes the steering feedback loop shudder and related Traction Control system faults. We'll find out and report back soon!
Cheers,