Anyone know what is the optimum (or at least a “good”) size for wheels and tires for track/road course use? What size and width? And what would be some examples of wheels/tires in those sizes? Thanks

 

wider tires = wider footprints = better traction
bigger sidewall = more air = more comfort
more sipes = more cuts in the tires = better traction in wet condition, also faster at releasing heat
bald tires are very good for traction on dry roads, hence the race track...but will f*ck u over in wet weather...

 

i too want to know if anyone has a real answer.
best motoring international compared a 35th anniversary vs a version st. the wider rim provided better stability and less oversteer.

i want to know what rim and tire sizes will give the Z the best performance and what the different characteristic of each choice will be. i.e. acceleration, over/understeer, etc.

 

I'm using 18x9.5 +22 with 275/35/18 for both front and rear. I've found this setup to be well balanced but I think the gearing for tighter more technical courses isn't quite up to par so I'm thinking about going to a set of 17x9.5 with 275/40/18 front and rear.

 

There is no single answer for that question. But some trends seem to point towards running same width tires all around with slightly wider rims in the 9.0-9.5 sizes.

Your final choice will also depend on the current and future setup you intend to run and of course your budget.

I do HPDE of full road courses. My track only wheel combo is:

5Zigen FN01R-C 17x9.0 +35 w/ 255/40R17 Toyo RA1 (front)
5Zigen FN01R-C 17x10.0 +35 w/ 275/40R17 Toyo RA1 (rear)

It’s a bit too much grip for a stock suspension though.

I’ve had fun with the OEM Track wheels with 235/40R18 (front) and 255/40R18 (rear) Falken Azenis RT-615 last year. That car was pretty well balanced and they served as a good dual use Street/Track setup.

 

The COMPOUND of the tire is going to make a LOT more difference than the WIDTH of the tire. If you go out there with 295 width all-seasons, you are going to have far less grip than with 255-width R-compounds. With that in mind, I'd choose the tire you want, and then select from the widths that would be close in proportion to the stock stagger.

Smaller diameter wheels will generally be lighter, so don't bother with 19's. 17" or 18" wheels will be fine. Honestly, I wouldn't worry a whole lot about the exact width, as long as it's in the general ballpark. You can dial in understeer/oversteer balance with careful adjusting of tire pressure. Just get a lot of trackday seat time under your belt. By the time you're up in the advanced group, you might get some idea of your own preferences -- whether you'd like a shorter sidewall for a crisper turn-in, or a slightly narrower rear tire so you can throttle-steer more easily...but for now, just get in the car and drive.

--Dan
Mach V
Fast350.com