froggy47

Thanks for looking. Do you need a spacer on the front? How much?

I know it'll rub a bit at full lock & maybe eat the duct (for brake cooling) and fender liner.

Other than that what do you suggest to run this setup?


Alignment change necessary from the usual 275/295 on 17's?

Thanks.

kmagvette

Yep, the tire will hit the brake duct. No worries about the fender liner since the fender itself will hit the tire...at least that is what happens with a stock suspension. Run long enough and it will clearance itself. The fender will develop a sharp edge, I hit it with a file to help the process along.

Krispy

With a 315/18" Toyo R888 will the tire stick out of the fender? By how much?

(assuming OE wheels)

Solo2GS

On GS (17 X 11) rims; other than going to full lock, I never had any problems with stock suspension and lowered on stock bolts... even lower with different springs there is no problems...

Fastguy

Its entirely dependent on the tire brand. I run Kumho V710's on the rear and Nitto NT-01's on the front and there is no issue at all even at full lock. If I swap from to rear, the Kumho's hit everything, fenderwell, brake duct, fender.

froggy47

So could you clear the fender lip if you raised up a bit? I really don't want to tear up the fender lip.

315 x 35 x 18 on a 18 x10.5 zo6 stock offset rim.


Maybe a 305 on front?

Fastguy

Just run Nittos and they will fit the front.

WNeal

I'm running Hoosier 315.30.18 all the way around on an 06 Coup.

did rub but cut out a bit of inner fender, 3 mm spacers and wheel lock installed.
No more rub

The Spark

I'm running 295 Hoosiers on 18" wheels on front and 315 Hoosiers on 18" wheels on the rear with no issues on C5. Lowered a little with Z06 springs. No fender rub. A little rub at full lock.

It looks like 315s would stick out too much on the front - but I haven't tried it.

Wah

I used to run 315/30/18 Pirelli PZero Corsa mounted to 18x10.5 rear wheel on all 4 corners on my '03. No problem with the brake ducts. The front wheels inner lip will contact the upper arms at full turns only. It was minor enough that I didn't care to make any clearance on the upper arms. I suppose I could have taken off just a hair of material on the upper arms w/o compromising its integrity.

LehmanZ06

You will be fine no height changes or alignment changes...

WBHighwind

My car is lowered and the only time I rub the fender is when I get over aggressive and hit a curb at the track. Otherwise I have no problems as long as Im careful not to go to full lock in the pits.

Bill Dearborn

I just started running Hoosier 315/30/18 at all 4 corners on OEM Z06 18x10.5 wheels. The car is not lowered. The 315/30/18 is almost the same diameter of the 315/35/17 so there are no real clearance issues except the DRM brake duct. I ran 2 track days at Watkins Glen this week and did not have any clearance issues unless I turned the steering hard left or right. When I ran GS offset 17x11 wheels front and rear the inside of the rim would rub on the control arm and rip off any balance weights that were installed while the tire would rub the brake duct. Kumho doesn't make a 315/30/18 tire so their 315/35/18 tire diameter is about an inch more than the Hoosier and you could get some definite clearance issues with that tire. The Kumho 305/35/18 is the same diameter as the 315 Hoosier.

Biggest problem with running the Hoosiers is probably getting sufficient camber to keep from cording the outside of the tire. This is made worse due to running the 10.5 rim which is a half inch smaller than Hoosier's minimum recommended rim width. Will know shortly whether or not they last. Have another driving school this weekend and then 4 autocrosses the following weekend followed by a track day at Pocono on the 21st. I am going to keep moving the tires from front to rear and side to side to try and minimize the wear.

Bill

Solo2GS

If you are not lowered beyond what the stock bolts can lower I do not see how there can be an issue with hitting the fender lip regardless or what size tire or rim width? There is a lot of gap there!

My 315's stick out a bit and I have never hit the fender lip!



How low are you?

jadkins

I am running 17x11s GS clones with Kuhmo 710s - 315s square - on my 2008 C6 z51 (w/downsized C5/C6 brakes) - and ONLY get rub at FULL LOCK. I do NOT have brake ducts - but my Dad also runs this same wheel on the front of his 2003 Z06 and has to be carefull at full lock as well since he does have brake ducts. But that is the only time there are any issues.

I have gone with the 17x315 just because Kuhmo, Hoosier, Nitto - all make track tires - they are a little cheaper than 18s and since they are square I can rotate them all season.

GrantB

I'm going to be running OE C5 Z06 wheels on the front of my C5, and it will see a lot of street use (hopefully in the One Lap next year). Does anyone make steering stops that will keep the tire from rubbing DRM ducts?

I could just be careful with it - but my dumb *** would probably forget one day and end up tearing the ducts off during a u-turn or something.

ssdeuce

I have recently bought a track set of CCW classic's that are 18X12 for all 4 and have 315/30's. They stick out about 1" maybe. But was only warned about turning them full lock with brake ducts. Should I be worried about the fender hitting during track days? I don't want to bust up my fenders.

froggy47

Just stock bolt low, I have a LOT of gap. I think I'd be ok.

gkmccready

My '06 Coupe with 295/30r18 Toyo R888s on CCW 18x11s rub the fender. Eventually rubbing away about 3/8" of the tire and filling the gap between the inner and outer fender with rubber.

I have no idea why my car seems to be special, but the way it is I can't imagine fitting a 315. I'm actually thinking of getting 18x10s and running a 275 tire to clear the fender better...

GrantB

Is a beefier PS cooler needed for using OE Z06 rears in the front with 315s and 9 degrees caster? I never had a problem with the stock C5 FRC cooler with 275s in front, but I'm wondering if I should put a larger one in there? Might it help the pump and rack live longer, or is it a waste of time?

Tru Cool makes a 4x6x3/4" PS cooler for only $30, and it should work much better than the Z51/Z06 tube-fin design (which is 3x12.5x7/8").