Ideal size width and weight for max performance

[Boofneenee]

Hello all, after spending A few mos scouring the engine and exhaust forums for info to guide my purchasing decisions i have recently turned my attention towards my goal of owning new wheels and tires.
I am doing this because i have come to the realization that the correct wheels and tires can significantly impact my cars performance. You should know that performance is all i care about. I could give seven shits about asthetics.
This is my dd, i do not autocross i drive it on smooth roads and cautiously on bumpy roads. My suspension is stock and it will stay that way. I am shoppig for performance light weight wheels and matching tires that willd fit my stock suspension all while creating the greatest performance gains. Decreasing unsprung weight is key for me but i also understand that more grip aids in acceleration and turning.

My question to anyone who cares to help me. What is the ideal wheel and tire size, weight and width for this car on stock suspension?

[1Cor10:23]

also interested in responses...subbing

[Draco-REX]

I ran a set of sticky (Advan AD08) 235/40-17s on my BRZ with lightweight 17x8 Wedsport TC105n wheels. I think they were a great setup in both reduction of unsprung weight (-2lbs per corner) and in added grip. I used them for twisty back roads, AutoX, and even a track day. I was never left wanting.

You could go with an even lighter tire, but you'll lose some feedback and response due to thinner sidewalls.

Stock weights are 20lbs for the wheel and 21lbs for the tire. So a 15lb wheel (17" TC105n, or RPF1 for examples) and a 24lb "Extreme Performance" tire (Advan AD08, Direzza ZII) will work very well in my experience.

[Draco-REX]

Oh another note. With the added stickiness on stock suspension I found some bad behaviour with the stock suspension when pushed to the limits. I would recommend at a *minimum* a set of crash bolts from Subaru to get some negative camber on the front. Zero out the toe and you won't see any increased tire wear.

[diss7]

I use 205/40/17 semi slicks on 17x7.5 se37k

Shortens the gearing a little bit. Heaps of grip. One of the lightest setups you can get really. 14.7kg 32.4lbs

[diss7]

Originally Posted by Draco-REX

Oh another note. With the added stickiness on stock suspension I found some bad behaviour with the stock suspension when pushed to the limits. I would recommend at a *minimum* a set of crash bolts from Subaru to get some negative camber on the front. Zero out the toe and you won't see any increased tire wear.

Agree on the camber bolts, disagree regarding toe. The toe out present on the front aids turn in. Depending on the type of driving / speed of corners you attack, will govern how much toe out to have. The toe in at the rear is present to aid stability under heavy braking.

I used to be a zero toe fan as well, until I did it, then tested it at the track.

[Draco-REX]

Originally Posted by diss7

Agree on the camber bolts, disagree regarding toe. The toe out present on the front aids turn in. Depending on the type of driving / speed of corners you attack, will govern how much toe out to have. The toe in at the rear is present to aid stability under heavy braking.

I used to be a zero toe fan as well, until I did it, then tested it at the track.

True, but the OP doesn't track/autox his car at all. So zero front toe would help keep highway wander to a minimum without deadening his steering as toe-in would. Toe-in at the rear might be a good idea for the FR-S' tail-happy setup.

[jvincent]

If you check out the following thread in the tracking sub-forum, you'll see from the guys that go really fast that 225/45 on light 17x8 is probably the best combo.

http://www.ft86club.com/forums/showthread.php?t=32423