305s can fit all around, I have done so on 10" RPF1 +38 wheels, though you'll need some front spacers. It will not (easily) work with the 10.5 +15 RPF1 wheels. These are the Kumho V710 autox tire, as Hoosiers do not come in 305. Making a 315 work in the rear is cake, making it fit in the front is another challenge, but I'm working on it.

 

Updated post #21 with some pics.

 

Very nice! I can't wait to run a fat square setup. Looking really good Scott.

 

Scott, so are you saying it would be pretty difficult to run an 18X10.5 RPF1 with a 315 on +15 offset? even with spacers? is that just because of the fender hitting the tire or suspension parts? if its the fender then i may be interested in trying it out!

 

17X9 MB weapons, RS3 255/40/17, Eibach sportlines, Kinetix a-arms.
Cars well balanced and a lot of fun.

https://my350z.com/forum/attachment....1&d=1316732143


Difference between 245/40/18 and 255/40/17 RS3's Hancook really stretched the sizing on the 255
https://my350z.com/forum/attachment....1&d=1316732143

https://my350z.com/forum/attachment....1&d=1316732143

PCA autocross 2nd best time overall behind C5 vette on R-comps
http://youtu.be/7Ydl6KGbxIc

 

Better contact patch on corner exit, resulting in being able to put the power down earlier and harder. Steve Mitchell (M-Works) runs slightly over -1 on his car.

 

255/40/17 RS3s FTW! $125 a tire, cant beat it!
thats why I want 17x9.5 +18 RPF1s

 

Yep its a great deal, you gearing shortens a bit due to a shorter overall tire but not bad. I am about 4 mph less at 60(indicated) than the stock size.

Looking at the specs on tire rack and the 255/17 width is only one/tenth of an inch less than the 285/18 RS3. Pretty good deal.

 

Going strictly by the bolded, wouldn't it make more sense to have less camber on a higher HP car than the lower HP then, not the other way around, so that you have more contact patch on corner exit? I'm still not getting why you want less neg camber with lower HP car or why the HP even matters with respect to camber. I'm saying with all other factors, like weight, suspension, etc being equal of course.

 

17x8.5 rpfs running 255/40 RS3s (love this tire!)

18x9.5 rpfs running a048s but might try R6s next year. Will only use for competition if they can shave enough time off.

 

3 5 0 did you just miss read terrasmak quote at top. He is saying the same thing you are. High HP = less neg camber for a flatter contact patch.

 

Ditched my 19's and installed these today...

SSR Type F -
18x9.5 +12 w/ 10mm Spacer - 255/35/18
18x10.5 +15 - 295/35/18

Toyo T1R's for now, hopefully get some R6's for Christmas...

 

With less camber you sacrifice corner speed but gain added traction for straight line acceleration. More camber = less contact patch for forward acceleration.

The sooner you can go to WOT the better, expecially for a high HP car. An NA Z is a cross between a point and shoot car and a momentum car. An example, S2K is more of a momentum car than a Z, also uses more rear camber.

 

ROFL! Thank you for pointing out my inability to read.

 

17x10" +35 5zigen FN01R-c with 275/40/17 Kumho XS all around
15mm front / 20mm rear spacers mostly because they make my DD wheels fit better. I plan to go to 295/35 Kumho XS all around next season and will probably need slightly smaller spacers.

 

Any particular reason why you don't want to try a different tire?

 

None of the other "good" street tires are made that wide in a 17 except for the Nitto NT05 which I haven't heard great things about. I'll eventually go to Hoosiers, but since I just seriously got into autox this year I want to stay on street tires for a couple seasons.

 

 

why so many stickers?

 

....adds horsepower.