Shaping up a new-to-me 07 GT3
#136
I ran .2 front springs and .1 rear springs on stock shocks with TPC front bar 1 hole from full stiff and .1 rear bar middle hole. Last Summer, on my previous 997(450/720 springs, TPC front/.1 rear bar), I tried full soft rear bar for one track event when the track was scorching hot and I was fighting for rear grip in one section of the track. I got the rear grip but it pushed. That particular event was more advantageous to have the rear grip and deal with the push. I have seen on a number of race cars they run full soft rear for most race events, but those drivers are racing and braking into the turns MUCH harder than I am driving in DE's. To give you an idea on stiffness, TPC front bar is ~50% stiffer than the .1 front bar compared in the middle hole. The .2 front bar is a good bit stiffer than the .1, the .2 bar doesn't have a middle hole as it has 4 holes, it is still a tad softer than the TPC bar overall. Of the 997's that are racing in Continental Tire Sportscar Challenge, Rum Bum Racing is the only team using TPC front bar. We like to think it contributed to their series championship. The answer for your question- I kept the sway bar settings the same with the new shocks and springs. It is my opinion that these cars(.1 and .2) are undersprung in the front from the factory. These cars will almost always benefit by using stiffer front springs to a point(which is why DSC helps a lot by stiffening the dampening, even with stock springs), especially when the front camber is in or above the 2-degree range. It has been my approach which I learned from TPC Racing to think of the effects from front-to-back and diagonal. To me, stiffer front springs not only help with braking stability, it also helps with coming off the throttle to make the transition smoother and transfers weight better to the rear. Unless of course it is so stiff that it overwhelms the tires. Which is not the case here in my very streetable car. The next track event in this car is in mid-July. If there will be excessive push on exit, my approach then would be to Not soften the front bar, but instead stiffen the rear bar one hole. Or buy a TPC rear bar which has 4 holes instead of 3 for higher rear bar tuning resolution with the extra hole. Softening the front bar will make the car spin more easily at the limit. Again, this is just my approach. Other teams and drivers have their own approaches and preferences. You have to do what works for you.
Enrique
#137
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From: Jessup, MD
Yep, I currently use the OEM out tie-rod, so I can use your's. Thanks for all the legwork on the toe-curve, I certainly plan on using that information, and will either get a whole TPC set, or just the outer tie rods.
I use locking plates on the inside of the toe-links (instead of eccentric), which I believe sets them at the same 6-oclock position, but I need to confirm.
I use locking plates on the inside of the toe-links (instead of eccentric), which I believe sets them at the same 6-oclock position, but I need to confirm.
Your lock plate bolt should be equivalent to 6 o'clock position unless the bolt hole on the lock plate is offset.
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TPC Racing stats:
2023 Porsche Sprint Challenge 992 Cup Am Champion
2023 Porsche Sprint Challenge GT4 Pro-Am Team Champion
2022 Porsche Sprint Challenge 992 Cup & 991 Cup Champion
2020 IMSA GT3 Cup Challenge 2nd Championship
2018 IMSA GT3 Cup Challenge 2nd Championship
2016 IMSA GT3 Cup Challenge Champion
2013 IMSA GT3 Cup Challenge Champion
2006 Rolex-24 @ Daytona GT Champion
2004 Grand-Am SGS Class Champion
PCA National Instructor
TPC Racing stats:
2023 Porsche Sprint Challenge 992 Cup Am Champion
2023 Porsche Sprint Challenge GT4 Pro-Am Team Champion
2022 Porsche Sprint Challenge 992 Cup & 991 Cup Champion
2020 IMSA GT3 Cup Challenge 2nd Championship
2018 IMSA GT3 Cup Challenge 2nd Championship
2016 IMSA GT3 Cup Challenge Champion
2013 IMSA GT3 Cup Challenge Champion
2006 Rolex-24 @ Daytona GT Champion
2004 Grand-Am SGS Class Champion
#139
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From: Jessup, MD
Sorry for the confusion. I will do my best to stay on topic and answer questions.
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Robocop305 (11-08-2023)
#140
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From: Jessup, MD
The .2 front spring is part # is 997 343 531 94. They are very pricey from the dealer and only marginally stiffer than .1 springs(see photo for actual in-lb rating). I used them because there was a pair in the shop's spring inventory that wasn't being used, which I eventually returned. If I were to buy front springs to match the stock .1 rears I'd go with something like 350 or 400. You'll need 9 inch tall springs at those rates. If you have access to metric size 60mm ID springs it'll be a direct swap. Metric size springs are harder to get here in the US so we convert to 2.25 inch ID which requires changing the spring hat and perch to make up of the difference of a measly 0.112 inch diameter.
Last edited by Tom@TPC Racing; 06-16-2014 at 10:21 AM. Reason: Forget to attach photo
#141
Thank you for the information. Any idea what the spring rate is on a 4.0 ? I was extremely lucky to drive one - the car rides perfect. How about using swift springs to stiffen up the front ? No reason to stiffen up the rear ? Ideally i would like to keep using oem parts.
Btw part number is 997 343 531 94 504 , price is $ 375.77 each.
4.0 part number is 99734353181 504 , price is $ $536.58 each. Any idea on this spring rate ?
Btw part number is 997 343 531 94 504 , price is $ 375.77 each.
4.0 part number is 99734353181 504 , price is $ $536.58 each. Any idea on this spring rate ?
The .2 front spring is part # is 997 343 531 94. They are very pricey from the dealer and only marginally stiffer than .1 springs(see photo for actual in-lb rating). I used them because there was a pair in the shop's spring inventory that wasn't being used, which I eventually returned. If I were to buy front springs to match the stock .1 rears I'd go with something like 350 or 400. You'll need 9 inch tall springs at those rates. If you have access to metric size 60mm ID springs it'll be a direct swap. Metric size springs are harder to get here in the US so we convert to 2.25 inch ID which requires changing the spring hat and perch to make up of the difference of a measly 0.112 inch diameter.
Last edited by F1CrazyDriver; 06-16-2014 at 12:55 PM.
#142
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From: Jessup, MD
Thank you for the information. Any idea what the spring rate is on a 4.0 ? I was extremely lucky to drive one - the car rides perfect. How about using swift springs to stiffen up the front ? No reason to stiffen up the rear ? Ideally i would like to keep using oem parts.
Btw part number is 997 343 531 94 504 , price is $ 375.77 each.
4.0 part number is 99734353181 504 , price is $ $536.58 each. Any idea on this spring rate ?
Btw part number is 997 343 531 94 504 , price is $ 375.77 each.
4.0 part number is 99734353181 504 , price is $ $536.58 each. Any idea on this spring rate ?
#143
Ok, I've got a very important question that was posed twice but not answered: what did you use to clean up the alcantara? That dirty shirt makes me think I should give my interior a go!
#144
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From: Jessup, MD
#147
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From: Jessup, MD
Just before I decided the clean my steering wheel, shift ****, and seats, I did a quick internet search to find a factory approved cleaning product. None was found. I did come across a BMW branded product which I phoned the local dealer and they said it was pulled from the shelves. So I figured F* it and just grab the white t-shirt and a bucket of water and went to town. As a grassroots mechanic I never know when I'm going to crawl on the ground so I always keep an extra shirt in the trunk in case I need to get carry-out from a restaurant or something afterwards. The extra shirt turned out to be extra useful this time.
#148
Not to highjack your thread, but i have used this to clean my interior for many years and it does wonders:
http://www.griotsgarage.com/product/...r+35+ounces.do
http://www.griotsgarage.com/product/...r+35+ounces.do
#150
The questions in this thread are around the cleaning of the alcantara, Leatherique would NOT be a good option for this.
I used a cloth dampened with warm water and a second cloth to buff dry the shifter on my car and as the OP suggested, it worked very well.
I used a cloth dampened with warm water and a second cloth to buff dry the shifter on my car and as the OP suggested, it worked very well.