275/295 RT660 Autocross, Rub?

[Al.B]

New car, first post. Been running larger re71, rt660 on previous C6 corvette for the last couple years but new to the mk5 Supra platform. I wanted to run 275/295 rt660 on the factory wheels, they are about the size of the average 285/305. Anyone running this setup and I’m hoping to hear no rubbing? I searched before posting for an answer without luck.

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[Pito]

I'm in the same boat. Here for the info

 

[Evolution]

Those tires are too wide for a factory wheel. I mean ya they will fit but there really won't be any benefit to them besides straight line traction. You really need wider wheels to get the most out of them in autocross. I would prefer stock sizes (which will still be wider since the 660s run wide) at that point. I run a 295/315 setup with aftermarket wheels with no rubbing issues.

 

[Al.B]

Since I was more concerned with the front rubbing under hard cornering, I went with 265/295-35-19 rt660 and maybe it might be the better choice for these stock wheels. Rt660 265/295 is 9.8/10.6 tread width and the diameter difference is also pretty close to stock. A little big for the stock 9/10 wheels but should be good for autocross. For street class where you’re restricted to the stock wheel width it’s common to run a 0.5-1” wider tire (tread width). Some go even bigger but I don’t like to exceed an inch over. Ideally you don’t want to exceed the rim width at all for proper sidewall support but there are grip benifits to doing so. I’m talking in general, I don’t know much about the Supra. My tires come in today but I won’t get to run them till the 27th, I’ll report back then.

 

[zrk]

straight line traction

Are there other types?

 

[OneTimeAccount]

Since I was more concerned with the front rubbing under hard cornering, I went with 265/295-35-19 rt660 and maybe it might be the better choice for these stock wheels. Rt660 265/295 is 9.8/10.6 tread width and the diameter difference is also pretty close to stock. A little big for the stock 9/10 wheels but should be good for autocross. For street class where you’re restricted to the stock wheel width it’s common to run a 0.5-1” wider tire (tread width). Some go even bigger but I don’t like to exceed an inch over. Ideally you don’t want to exceed the rim width at all for proper sidewall support but there are grip benifits to doing so. I’m talking in general, I don’t know much about the Supra. My tires come in today but I won’t get to run them till the 27th, I’ll report back then.

Stock suspension and not lowered? If so you might not rub the fender.

When I ran 275 A052’s up front with my Apex EC-7R wheels (10.5” wide), I needed a 12mm spacer to clear the strut assembly. But then the tires rubbed the fender terribly. I had to change to HKS adjustable lowering springs that had a smaller diameter spring perch, allowing me to ditch the spacer and not worry about the tires rubbing against the perch.

Not sure how it will work with OEM wheels and a wider tire. Just something to pay attention to. Curious to know what you find out.

 

[Evolution]

Are there other types?

I dont know if your car came equipped with one but mine has a device called a steering wheel. It does things, fun things.

 

[zrk]

I dont know if your car came equipped with one but mine has a device called a steering wheel. It does things, fun things.

Ehh.. I don't think I have that? Is it inside the drag radials?

 

[OneTimeAccount]

Ehh.. I don't think I have that? Is it inside the drag radials?

What are drag radials?

 

[Evolution]

What are drag radials?

Im not sure but they sound boring....

 

[mikereyesboss]

I’m running Titan 7 TS5 Square 18x10.7 +38 with 295/35/18 A052’s and no rubbing.

-3.5 front, -2.5 rear on HKS adjustable springs.

 

[suicidaleggroll]

Since I was more concerned with the front rubbing under hard cornering, I went with 265/295-35-19 rt660
...
My tires come in today but I won’t get to run them till the 27th, I’ll report back then.

So how did it go?

 

[Al.B]

Ax event. No issues. No rub. RT660 265/295-35-19 balance felt just like the stock tires. It should since there was about the same difference between front and rear tread width as stock. The tires don’t even look that pinched, maybe just a little, but as far as clearance there’s plenty space for this size. On stock wheels, stock springs and no spacers.

 

[Al.B]

This is how 265/295 looks on stock rims.

 

[tire.eater]

This is how 265/295 looks on stock rims.

Exactly what I'm currently looking at doing, thanks for the thread. What kinda camber are you running with?

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