Project Update for July 17th, 2014: Wow, I'm so behind. I wrote most of this entry two weeks ago but was waiting for some pictures and got busy doing other things. It ran long so I pulled a few events out and will show them in the next update. In this build thread entry we show upgrades to the TT3 Mustang after ECR, including a new driveshaft, new tires, new brake fluid, aluminum lower rear wheel spats added, and more. Then we cover the NASA at Hallett event write-up. the car was overheating (explained below), a bit pushy with too much wing, and we got rain in final CW session laps. Then we will talk about stuff for the next entry.
More TT3 Mustang Updates + New Parts
At long last we have ditched the stock 2-piece driveshaft and center bearing and replaced it with a 1-piece aluminum driveshaft. We used a Driveshaft Shop aluminum 3.5" diamet6er unit with a CV joint at the front, which is rated at 1000 hp.
So, how much weight did this save us? Sadly, I don't
really know. My shop guys forgot to weigh the new and old driveshafts when they did the swap - it was a hectic thrash to get ready for Hallett and weighing this was overlooked. The Driveshaft Shop website shows this to weigh 19 pounds, but you know how I trust everything I read on the interweb.
The stock 2-piece driveshaft on the 2011-14 GT/Boss is HEAVY
The old stock driveshaft was still here so I just had our guys weigh it today. A hair over 37 pounds, so this upgrade
might have lost 18 or so pounds, if the stated weight of the 1-piece unit is correct. Driving the car after this mod produced no adverse effects, or any noticeable benefits. A customer sold this one to us after we did a Tremec Magnum XL swap for the stock Getrag MT-82, so it was a cheap upgrade for us. We actually sell Dynotech Engineering driveshafts and will get them on our website
eventually.
I've spoken about the upgrade we made to the 4" brake ducts at the front bumper opening and the hoses but before we ran the ECR test we ran out of time to make the new 4" ducted backing plates. Well now we had the time, and engineer Jason had procured a new Ford part number to test with. This OEM stamped steel backing plate is a different diameter than the one we used for previous batches of 3" ducted plates (based off the 14" Brembo equipped cars) and turns out it was easier to use with the 4" hole than the smaller 3" hole, plus it had some other advantages.
This different OEM backing plate version has a deeper dish to the hub clearance area which allows for more even flow inside the rotor ring itself, and should get more air to the hub bearing. We have tried 4 different backing plates from various S197 cars and this one fits the tightest to the rotor and has more room inside to spread air to the right places, so we've switched ALL of our S197 ducted backing plates to this new part number. We have a big batch of the OEM back plates being bead blasted this week so we'll make a run of these 4" ducted plates soon and put them in the same section as the 3" plates. The production 4" plates will have an oval duct on the backing plate, and not round like the prototypes built for our TT3 Mustang.
Again, unless you are KILLING your brakes and already have 3" ducted fronts, the 4" plates might be overkill
plus they require some additional front fascia work to attach the 4" hoses. And the stock windshield washer bottle is not possible with 4" hose, whereas a 3" will barely fits around it. Some folks do
like overkill, though. And you know me - I'm a hack driver and I tend to
overdrive everything, so I use more brakes than most. We checked the front caliper temps with a fresh set of Alcon temp strips at Hallett, to see if we could reduce the max temp from 490°F we were seeing before with 3" and 430°F we saw at ECR with 4" front openings and hoses but the 3" backing plate ducts, and I will talk about the gains we saw below in the race report.
Towing and Strapping Down an S197
Whether you tow or drive your car to a race track, or what your choice of tow vehicles is, are two discussion I try NEVER want to wade into. These are no-win arguments that will put people against one another looking for blood, like the Hatfields and McCoys! But if you've made the decision to start towing your car to the track instead of
driving it to the track, which does relieve a LOT of stress and allows you to focus on your driving and pushing the car rather than saving enough brakes and tires to get you home, there are some new things to learn.
When towing one of my
least favorite things after a long race weekend is loading the car into the trailer and strapping it down. Every car has a "trick" or two that you might learn from someone else. Like when it comes to E30/36/46 BMWs, which I have towed hundreds of times, I tow them via "T-hooks" slotted into the 4 factory under-chassis slots (hidden under 4 plastic jacking point pucks) and I will
always cross both the front and rear straps. On the S197 Mustang, it has its own set of tricks to strapping the car down safely. I've seen some janky set-ups and have learned what to do (and not) over the years by watching others' tow their cars.
The front is relatively easy, as we use 3" ratchet straps with a C-hook end and "hook" into some big slots in the front lower subframe structure. The same "T" hook ends also work here very well. But when towing inside an enclosed trailer it takes some finesse to throw the straps under the car to where you can reach them behind the wheel and then you have to hook them into the slots blind, but once you've done it before its fairly easy.
Left: Mac's Custom Tie-downs are my favorite. Right: I hate strapping through wheels, but these padded axle straps "could" work
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