bky

I'm looking for a good front tire size. I like the Kumho SPT for daily driving, and the size selection is great. I have plenty of R-comps for track and solo use, and liek the life/grip/price compromise of the SPT.

I've always like the balance of smaller front tires, like my current street setup of 205F/245R on OEM 16". I find it makes the car easier to drive, and I think a lot of people run too much front tire on the stock suspension. I've run 225F/275 Kumho MX and loved them (on 17x8+48, 17x9+63) because the car was so easy to recover. Big stagger seems to make the car easier to drive.

Anyway, I'm trying to figure out what I'm going to do in front. I've got the stock sway bar, 380lb springs, and adjustable perches. I'm going to roll everything for more clearance, and plan on bigger sways all around (eventually). I'm entertaining the idea of running a 17x8+45 all around, and looking at tire sizes for that wheel. This is what the Tire Rack lists for the SPT:

205/40ZR17, section width 8.3", diameter 23.5"
205/45ZR17, section width 8.1", diameter 24.2"
205/50ZR17, section width 8.5", diameter 25.1"
215/40ZR17, section width 8.6", diameter 23.8"
215/45ZR17", section width 8.4", diameter 24.6"
215/50ZR17, section width 8.9", diameter 25.5"

My rear tire will probably be the:
245/40ZR17, section width 9.8", diameter 24.7"
Close to the stock diameter. Another option is the:
245/45ZR17, section width 9.6", diameter 25.7"
This tire would ride a bit better from the taller sidewall, but the diameter is a bit more than stock.
I have the stock rear sway bar and 340 lbs springs in the rear. I can run whatever camber I need to. I think the 40 series is best for me in back.

Questions: which front tire should I run with the 245/40ZR17 rear?
Does running a smaller diameter front tire compared to the rear mess up the ABS?

I'm liking the 205/45 front right now. Opinions?

silentdancer

215/45ZR17", section width 8.4", diameter 24.6"
245/40ZR17, section width 9.8", diameter 24.7"

do not run a 205/45 in the front.

iqbal624

they also make a 225/45/17 for the front
and a 255/40/17.
i had that setup on my last S.

bky

Why not?

Sinji

too narrow for the front. I would suggest running 225/45 in the front

bky

Why exactly is it too narrow?

silentdancer

the stock ap2 runs 215/45's. they do run a little narrow but just stick to 215. you usually go like this...

215-245
225-255

Jim@tirerack

With the 17X8 ET 48 wheel the 215/45R17 would be the safest fit. The 225/45R17 would work better with the 255/40R17 on the rear.
If I can help let me know.

bky

Thanks Jim. Do you know if it bothers the ABS system if the fronts are smaller in diameter than the rear?