drdrank

Do you like those Super Sports in the wet?

utkinpol

it would be great if anybody with 997 gt3 car could finally conduct this experiment with 275/315 NT01 tires and confirm if they do indeed cause any PSM/ABS related CELs or odd behavior or do not.

drdrank

The Greek has a 997.2 GT3 and is running NT01s. Not sure what size. Maybe ask him.

Mvez

Even if they do work fine, which has yet to be confirmed, I prefer more sidewall than the 315-30's give....ideally a 305-35 or 315-35 would be offered. More grip, more progressiveness, better handling.

Nitto is looking at adding these sizes, we need to keep harassing them for the 35 aspect ratio.

NorthVan

Why do you want to run such a wide front tire? I never had excessive understeer on my C2S. What am I missing?

utkinpol

with all due respect, i`ll beleive it when i`ll see it...

utkinpol

understeer, probably.

cup cars run practically same sizes in slicks, 280/320. ther is nothing wrong with wide front tire, at all. i tried my car with 245/335 once - it was undrivable no matter how i tried to adjust setup, and nittos 315 tire is almost as wide as RA1 335. i balance my car to the limit where it slides on all 4 points in the sweeper as i push it with throttle, with just a bit of understeer.with 245/335 i could not do it, with 245/305 it did not have nearly enough grip in rear, 275/335 works perfectly fine.

NorthVan

Typically Cup cars run 240/640/18 fronts and 280/680/18 rears, but it depends on the series.

utkinpol

240/280 is on 9/11 rims, for 10/12 or 11/13 - 280/320.

if i will get annoyed enough this season with my front axle i will replace my front rims to some wider ones as 275 tire on 9" rim is not optimal. 265 tire would be better but NT01 does not have it, nor 255.

NorthVan

"We run these on the 2010 Cup with 9.5 fronts and 12 rears."

This is a quote from a major team, as well they post on RL on a regular basis.

Mvez

305 is more than enough tire for the rear.

The Greek

I am actually running NT01 245/40/18's upfront, but 305/35/18 rear in RA1's.

Finding RA1 fronts is impossible, so this was the best alternative. Tire grip is very close. No problems with ABS or PASM.

TRAKCAR

I don't know about heat cycling, but I corded them as quick as Hoosiers.
As soon as profile is gone, they have zero grip and cord immediately after.

So to me it's Hoosiers if you cant make Nitto's or RA1's work.

utkinpol

not all 305s are same. like in NT555r2 305 tire is 12.48" wide (almost 315 dot), nt01 315 tire is just 12.6" wide but has shorter stiffer sidewalls. ra1 335 tire i have now is 26" tall and is 13.3" wide. so it is an inch over 305 tire and 0.3" shorter.

then you look at 245 width - 9.72" compared to 275 10.9" and look at ratios you want to have on your car. 240/280=0.85, 280/320=0.875.

so we can presume for 2" split between front/rear rims in width we would want somewhat close to 0.86 ratio between front and rear tire width.

that was my logic, anyway, and that is how 275/315 in NT01 lineup gets binded together nicely as itis quite close to that.
if you go with nt01 245 tire in front then you need 287mm wide tire in rear to stay within target ratio and there in no such tire in nitto lineup, 305 tire is 316mm, it will be 0.78 ratio.

997gt3north

yes
- 235/35/19
- section width is 10.2 inches - i.e. 259mm - i.e it looks and is wider than a 'normal' 235 tire
- the actual tread width itself is 9.3 inches or 236mm
- 'they say' optimally you want the rim width from a maximum contact patch perspective to be basically the width of the actual tread to possibly slightly larger BUT this tire does absolutely fit on a stock 8.5 width front rim

I had pro David Empringham drive my car with a set of new R6s (235/315 in 19s) and he said the car was perfect - the speed he took me around Mosport with these tires was insane - 2:32 with me in the car

http://www.tirerack.com/tires/tires....R9R6&tab=Specs