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Tuning an FC for track use

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Old 02-09-18, 01:17 PM
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Tuning an FC for track use

What differential, suspension, sway bars and wheels should I get if I want to set an FC up for road course? I still want to be able to slide around a little bit but mainly to be fast.
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Old 02-11-18, 10:39 AM
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for the diff start with a stock limited slip unit, the S4 is a clutch type.

for wheels, the non turbo engine likes basically the shortest thing you can find. most are on a 15x7, or a 15x8 with a 205/50/15 or a 225/50/15.

for suspension typically people run 8/6 springs (its 450/350?), this is good at the track, but on the street 7/5 might be a better option.

not sure what shocks are out there at the moment, but actual racers would go for Bilsteins, or maybe something even higher dollar. i have a set of teins in mine, and its ok on the street, but they would need a revalve for the track (they almost need it for the street)

sway bars really aren't needed on the FC, if you must just get the RB front bar. the way the car is built, the sway bar has a lot of leverage and it actually is twisting the chassis a little, and putting a larger bar is just going to tweak the body more.
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Old 02-11-18, 03:54 PM
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If I were doing an FC, I'd mount the sway bar under the rear of the subframe so that it is stressing the firewall instead of the very end of the chassis.
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Old 02-11-18, 08:45 PM
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Originally Posted by peejay View Post
If I were doing an FC, I'd mount the sway bar under the rear of the subframe so that it is stressing the firewall instead of the very end of the chassis.
If I were doing an FC I'd run no sway bar and just put 1100 lb/in springs on it


in regards to the original poster:
23" tires (15x8s w/ 225/45/15s)
stock 86-88 clutch type diff
racing beat sway bars (maybe just the front, depends on driving style)
ground control koni based coilovers w/ 450/300 springs

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Old 02-17-18, 08:54 PM
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Like the others said, you shouldn't need the rear swaybar. I have a Ground Control suspension with adjustable camber plates, don't remember the spring rates but GC is really good, just give them a call and tell them what you are doing and they will recommend the best package for your needs. I run 15" wheels, if you can find them, the BBS wheels from the verts are very light, but really any of the stock 15" wheels are a decent choice. I've known people that use the mesh Jeep wheels, but I think they are a little heavier than stock wheels. I run SM7 Hoosiers, 205/50, you can usually find decent takeoffs if you can't afford new. Find a limited slip from someone parting out a car.
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Old 03-06-18, 07:41 AM
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thank you all members for help
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Old 04-04-18, 12:22 AM
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Originally Posted by j9fd3s View Post
for the diff start with a stock limited slip unit, the S4 is a clutch type.

for wheels, the non turbo engine likes basically the shortest thing you can find. most are on a 15x7, or a 15x8 with a 205/50/15 or a 225/50/15.

for suspension typically people run 8/6 springs (its 450/350?), this is good at the track, but on the street 7/5 might be a better option.

not sure what shocks are out there at the moment, but actual racers would go for Bilsteins, or maybe something even higher dollar. i have a set of teins in mine, and its ok on the street, but they would need a revalve for the track (they almost need it for the street)

sway bars really aren't needed on the FC, if you must just get the RB front bar. the way the car is built, the sway bar has a lot of leverage and it actually is twisting the chassis a little, and putting a larger bar is just going to tweak the body more.
What Bilstein or Koni Inserts even fit in a stock FC strut tube? The market for off the shelf struts for the FC appears to be getting pretty dry. AWR Strut tubes are 300 something a piece, I'm not sure if I or any other hobbyist could pull off custom strut tubes and make it work well quite frankly.
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Old 04-07-18, 11:41 AM
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Originally Posted by FBorDie View Post
What Bilstein or Koni Inserts even fit in a stock FC strut tube? The market for off the shelf struts for the FC appears to be getting pretty dry. AWR Strut tubes are 300 something a piece, I'm not sure if I or any other hobbyist could pull off custom strut tubes and make it work well quite frankly.
https://cart.bilsteinus.com/details?id=3095981820212814247&fyv=true&Year=90069 09165409448465&Make=5917206599523487079&Model=9212 650385784236194&Submodel=8557149328568454118&Pos=F ront

custom strut tubes aren't too bad, its just a piece of DOM tubing with ears on it. the AWR ones you are paying for the out of the box-ness

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Old 04-07-18, 11:00 PM
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I had actually found those last night. Replacing the strut inserts and installing a weld on sleeve kit seems relatively straight forward as well. I'm sure I could figure it out with a little common sense.
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Old 04-08-18, 11:04 AM
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Originally Posted by FBorDie View Post
I had actually found those last night. Replacing the strut inserts and installing a weld on sleeve kit seems relatively straight forward as well. I'm sure I could figure it out with a little common sense.
it does come with instructions
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