MarkDFW

I have a 2012 grand sport with aftermarket sway bars and coilovers. I have a street/track compromise alignment. It is my daily driver and will see around 8 or 10 HPDE per year.

Curious what suspension mod(s) you feel I should make next that are the best bang for the buck while keeping the car steeetable? Camber kit? Control arm bushing kit? Spherical bearing kit looks great but only for a dedicated tack car.

jcsperson

Brakes?

RaleighSS

what are your goals as a driver or for the car? The 2012 gs is quite a car out of the factory ... Add coilovers and sways to the mix and with the right driver there will be few out there in street trim running faster. Have you added seats / harnesses ? Are you running R-comps ? How much seat time do you have ?

My point here is the setup you have is very capable ... ya may not need anything else just yet ... run her as is .. if ya have R- comps and find ya need more negative camber add plates ... stock bushings are good till ya push them out or they get worn then move to poly ...

the order of mods I tell all my students

Seat time
Seat time
Safety (seats / harnesses / hans)
Motor reliability improvements ... like on a C5 Z Accusump / Oil cooler ect (not sure any applies to the GS under warranty)
Good set of Track Tries and Track Pads
Seat time with that combo ...
Then mod from there as needed.

MarkDFW

I run carbotech xp12 front and xp10 rear. Calipers are currently stock but have Stoptech ST60 on the way for the front and will stick with OEM calipers for the rear for now.

MarkDFW

I just got CCW wheels with kumho v710 and it made a HUGE difference the other week. I will not run street tires again.

This is mostly a street car so aftermarket seats are low priority for now. I run with advanced group and instructors and my times are up there with people who have been driving for a while. Most of the guys who are faster have cars that are flat out faster, but that is not to say I am not leaving time on the track, as i know i am.

I am having Ron Davis radiator with oil cooler installed shortly since my oil was hitting almost 300 on a 70 degree day. I also have a cam, headers, CAI and tune. About 450 rwhp. Carbotech xp12/xp10 pads.

RaleighSS

cool deal ... sounds like you have it sorted out and have seat time. Camber plates would help ya dial in camber based on tire wear ... as I said before rubber bushings are good but they do deflect under high stress causing ya to loose some grip I moved to poly on mine and did notice a difference.

I know its a street car but seats did make me faster as I could concentrate on driving instead of holding myself in esp when i went to r-comps ....

MarkDFW

I agree a good seat would make a difference, but not as comfortable for daily driving or the occasional road trip. I went with Angel Pads for now. They give good lower body support and are probably a good compromise for a car that is primarily street vs track. Down the road if my car is dedicated to track, seat and harness will be the first mod.

Solofast

First, lose the compromise alignment.

If you are running 10 events a year you are overheating and punishing the outside of any good tire that you put on the car when you are on the track.

You need at a minimum -2 degrees of camber up front, and 1.5 in the rear. Mark the front tie rods and set the toe to 1/8 of an inch of toe in for the street and put in one full turn towards toe out on each side when you change to the track tires.

It is toe out that eats front tires on the street. Leave it toed in on the street and toe it out on the track. You will still get 20k miles off of most any decent street tire, and yes it will wear the inside a bit faster, but it won't eat tires by any means. If you are really paranoid about street tire wear you can flip the street tires on the rims every 10k miles.

You are giving up a lot of cornering speed, and you aren't going to get decent tire life on any R comps if you don't optimize the alignment on the track.

This one change will do more toward lap times than anything else you are talking about doing, and it will save you money since you will get a lot better life out of your track tires.

redtopz

Sounds like you are heading down that slippery slope. From someone who has been down that path looking back here is my recommendation. Keep your beautiful new grand sport a street car and go buy a C5 T1 corvette for $25k or less, fully track prepped with spare parts. You will have a much better and safer time on the track and on the street and probably save a lot of money in the process. Modding a car is throwing money away. You can always re-sell the T1 car later and recoupe your investment or if you have the interest you can start racing w2w. Good luck!

JeremyGSU

Man I'm there now. haha. I bought my street car and have been turning it into a track car. You are definitely right about the costs.

MarkDFW

I'm at a point now where I've got too much in it to stop and buy a dedicated track car. My plan a few years from now is to buy a truck and trailer. My car will see less street and more track time and I can trailer it around to other tracks.

redtopz

I know exactly where you are right now . My blue T1 car was a nice street car before I started converting it like you are. I learned quite a bit gradually modding it into a track car and have lots of good memories racing in it, but now I wish I kept it a street car. I purchased my ST2 car ready to race with crates of spare parts for $17,000 and it's faster than my T1 car.

MarkDFW

In hindsight it would have been cheaper to buy a used truck and trailer and a used purpose built track car. I had never gone to HPDE until earlier this year and now I am hooked. Live and learn.

RaleighSS

No worries ... run her as is keep up maint and have a good time ... quite a few of us who run street cars all the time..... run her dont abuse her and she should show ya a good time :-)