RedZero

I have a set of stretched tires on some wide wheels and want to know if I should look for something else or will I be able to use them in say STU.

Have a set of wheels that on a ruler read out 11" wide but may only be 10.5" wide wheels. I know for STU I'm limited to a 245 wide tire and I'm running a stretched 245x40ZR18 tire.

What are the down falls, risks, repercussions of running autocross on my current setup or do you think ill be ok? I've heard mixed reviews on running stretched tires and I need to know if I should buy two new tires for my current wheels or should I just be looking for new wheels?

I'm looking for edjucated opinions backed with experience if at all possible. Thanks guys.

Piro Fyre

iTrader: (23)

Biggest risk is that the tire will roll over and that the rim will hit the ground, especially with auto-x and very sticky tires like Hankook RS-3.

Smike

iTrader: (8)

An inch over what that tire was deigned for. 9.5 is the general max for that sized tire.

Unseating the bead from the wheel is the main issue and high rotational mass/unsprung weight.

For me, I'd sell for light weight wheels and get Z1* or RS3 tires.

RedZero

Correct me if i"m wrong please, but doesn't stretching it reduce the roll over? I guess if you did still manage to get some roll over I could run into some serious issues with breaking the bead or touching wheel to pavement.

Dallas J

iTrader: (1)

A good club would boot you at tech for having tires stretched that much. Its a risk to anyone working a corner and I for one as a safety would stop the event until the car was removed.

RedZero

So, you feel that its not very safe to try and run them then? lol

Noted...

RedZero

So what would be the most ideal Wheel and Tire combo be? If I'm buying something new i want to have a regret free and very final decision before i drop the cash.

17x8.5 +35 Enkei Racing RPF1 with the tirerack suggested 235/45ZR17 Hankook Ventus R-S3 or go with a 245/40ZR17? Or do i need a wider wheel to run a 245 tire? Suggestions?

Jim3142

iTrader: (2)

You can run a 245mm width tire on the stock wheels, which are 17x8, so they will be fine on a 17x8.5 wheel.

FJF

iTrader: (18)

Agreed.

grillpt

iTrader: (24)

Depending on the average course design in your region, you may want to go with a 245/45/17. That will give you just a touch longer gear than a 40 series due to the taller height. So if you find yourself up on the rev limiter often, go with a 45.

Just my .02

RedZero

I'm guessing they discontinued every color of the rpf1's except the silver and black? Id kill to find a vendor selling them in gold. It's never easy I tell you, its never easy.

RedZero

So wheres the limit on the stretch? Not the tire limit but the autocross / performance limit. I've had a couple of local trade offers and i don't know where to draw the line. Could i pull off a 245 x 9.5 wide stretch or is that still too much to be driving aggressively on. Should i be drawing the line at 8.5 to 9 inches instead? Whats the width limit I'm looking for here.

BriK

iTrader: (11)

9" is the commonly acknowledged limit for a 245 tire.

Dallas J

iTrader: (1)

Ive seen upwards of 9.5" using a 245 on an STU car but another inch is a lot more wheel. Id recommend no less than 265s.

sujinX

iTrader: (22)

Ur not legal in stu anyways with the 18" wheel. Unless that's a typo. 10.5" is a bit too wide. A friend of mine in stu is running 245 rs3 on 10" wide wheel. It's not stretched too bad, he dominates the Stu class.