987.1S to GT4 questions
01-04-2019, 09:08 PM
#1
Rennlist Member
Thread Starter
987.1S to GT4 questions
I am considering upgrading to a GT4. I want the bucket seats and no PCCBs as I will track the car 25-30 days a year. I’m aware of the third gear issue and also a couple of front strut issues, but with 1.5+ years of warranty left I am ok with this info. Is there anything else the car “needs” to be “track worthy” besides a harness/roll bar and 6point harness? Maybe Pagid yellow pads? I realize there are tons of mods but I’m hoping to drive it a few seasons before changing things. The 3rd through 5th gear ratio change seems like a great improvement but pricey. Is the stock LSD an issue so that the Guards Transmission one is “necessary”? TIA. I just want to budget for things and be reasonably satisfied.
Last edited by RobC4sX51; 01-04-2019 at 10:02 PM.
01-04-2019, 09:39 PM
#2
Three Wheelin'
Read through the forum's GT4 track wiki below for the basic info:
https://rennlist.com/forums/gt4/9323...etup-wiki.html
1) Technically you can run the car as is, nothing is strictly necessary. There is no harm in driving the car fairly stock a few times and then going from there to see what you need.
2) With 25-30 days, I would at least get the parts to optimize the alignment for less understeer and to improve tire wear
3) The stock brake pads will not last the entire year, so at that point you can get some more track oriented versions.
4) Harness is good if you feel you are moving around too much as well.
5) I think really hardcore track folks will say the stock LSD will wear out with enough use, so that kind of answers the question itself.
https://rennlist.com/forums/gt4/9323...etup-wiki.html
1) Technically you can run the car as is, nothing is strictly necessary. There is no harm in driving the car fairly stock a few times and then going from there to see what you need.
2) With 25-30 days, I would at least get the parts to optimize the alignment for less understeer and to improve tire wear
3) The stock brake pads will not last the entire year, so at that point you can get some more track oriented versions.
4) Harness is good if you feel you are moving around too much as well.
5) I think really hardcore track folks will say the stock LSD will wear out with enough use, so that kind of answers the question itself.
01-04-2019, 09:55 PM
#3
Rennlist Member
Thread Starter
Wow, thanks for the link! Amazing amount of info there. Exactly what I needed. Cheers!!
01-04-2019, 10:13 PM
#4
Agree that the track wiki has some good info. And running it stock for a few days is a good idea. From my experience a few thoughts-
30 track days for me in the GT4 would be about 8 sets of tires and the largest single expense. I've driven the Cup 2s and RE-71s in 20in. For a while the RE71 sizes were out of stock. Many have moved to 19in wheels but caliper clearance is tight.
You'll need parts to get more camber which is desirable. I used shims in front but that's all, and toe links in the rear.
Next is brakes -high temp fluid (SRF for me) and race pads are a good idea. I like the Ferodo DS1.11 but there are other options. Be aware that you'll likely crack the caliper piston "pucks" at some point and have to deal with rebuilding with titanium pucks or SS pistons. Stock rotors will crack fairly quickly. I swapped the fronts to AP J hooks. Or you can do a full upgrade with the Essex AP radical setup- but pricey.
I recently got the Cantrell roll/harness bar and happy with it and Schroth 6pt GT3 harness.
Best of luck
30 track days for me in the GT4 would be about 8 sets of tires and the largest single expense. I've driven the Cup 2s and RE-71s in 20in. For a while the RE71 sizes were out of stock. Many have moved to 19in wheels but caliper clearance is tight.
You'll need parts to get more camber which is desirable. I used shims in front but that's all, and toe links in the rear.
Next is brakes -high temp fluid (SRF for me) and race pads are a good idea. I like the Ferodo DS1.11 but there are other options. Be aware that you'll likely crack the caliper piston "pucks" at some point and have to deal with rebuilding with titanium pucks or SS pistons. Stock rotors will crack fairly quickly. I swapped the fronts to AP J hooks. Or you can do a full upgrade with the Essex AP radical setup- but pricey.
I recently got the Cantrell roll/harness bar and happy with it and Schroth 6pt GT3 harness.
Best of luck
01-05-2019, 10:04 AM
#5
I've got 44 track days on my GT4. Zedcat's experience seems to mirror mine with a few exceptions. I'm still running OEM rotors and think they "may" last another season. I tried OZ 19" wheels and switched to CCW which solved the caliper clearance issue. I initially added camber with LCA shims only, last season I added camber plates to fix a caster and occasional fender rub issue (partly caused by lowering front ride height to fix rake). The biggest handling issue was rear stability under hard braking. This is fixed with additional rear toe and aftermarket rear toe links which are also needed to get proper rear camber. My LSD failed in second season. Car still understeers running full stiff rear bar and full soft front bar, needs more camber but is street driven.
Trending Topics
01-05-2019, 08:40 PM
#8
01-14-2019, 11:34 PM
#9
Rennlist Member
Thread Starter
Another question if I may: I have read a lot of threads recommending 19” wheels for the track. I understand the stock offsets are 61F and 50R. I have a set of 997 wide body 19” wheels that are 8” front and 57 offset, and 11” rear with 51 offset. These should work on the steel brake GT4s, right? Would a 245 work ok for the track on the 8” front or would it be better to go down to a 235? TIA
01-15-2019, 11:25 PM
#11
Rennlist Member
Thread Starter
of course! Already priced and factored that in. Cantrell cage is $2500, Schroth 6 point is $500. So $3k plus the car and I’m dancing. Thx
01-16-2019, 10:44 AM
#12
Rennlist Member
I would count on some camber plates and/or shims for the front and toe links for the rear so you can get a proper track alignment done. My car ate front tires quickly until I got a track alignment (3.0 degrees negative up front, 2.5 degrees negative at the back works for my car).