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rpf1
18x9.5+15 F: 225/40
18x10.5+15 R: 255/35
:smile2:
 

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18x9.5+20 really curious about 19s, just got some 19x10.5+20 in and wheel need spacers not to rub my shortened spindles and the test fit was crazy aggressive. plan on pulling quarters to tuck my current set up so wondering if I should roll my fresh fenders and make this work, not sure if any other problems will occur looking for some info .
133078
 

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I’m super new. Never posted before. I saw a guy on here in an older thread with a set up that looked great. He was running a nice 5 spoke concave 18x10 on the rear with 285/30’s! My buddy is rolling and pulling my fenders at his body shop. What offset would I need to pull that off and any other mods? Thanks
 

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So here's where I'm headed, have a pretty good idea of what I need based off measurements but would like to confirm.

Looking to do a 17x8.5 + 38 square setup with 255/40/17 square. About -2 degrees camber all around, can bump up to -3 or so but no more.

I'm not crazy low, I'm keeping my front ride height and lowering the rear about .5". My car will have fairly stiff coilovers as it's a track car.

Took some measurements today and what I'm seeing is that the rear will sit just about perfectly flush with no interference. The front will stick out past the fender about 5mm but will have clearance on the inside of the wheel.

So basically I think I'll need a 5mm roll up front, and most likely to re-mold the inner fender liner a bit. Seem about right?

1: Aggressive. Track fitment.
2: 17x8.5 + 38 w/ 255/40/17 square
3: Willing to make the front fit, don't wan't to go nuts and crack my fender paint
4: see above

133245
 

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So here's where I'm headed, have a pretty good idea of what I need based off measurements but would like to confirm.

Looking to do a 17x8.5 + 38 square setup with 255/40/17 square. About -2 degrees camber all around, can bump up to -3 or so but no more.

I'm not crazy low, I'm keeping my front ride height and lowering the rear about .5". My car will have fairly stiff coilovers as it's a track car.

Took some measurements today and what I'm seeing is that the rear will sit just about perfectly flush with no interference. The front will stick out past the fender about 5mm but will have clearance on the inside of the wheel.

So basically I think I'll need a 5mm roll up front, and most likely to re-mold the inner fender liner a bit. Seem about right?

1: Aggressive. Track fitment.
2: 17x8.5 + 38 w/ 255/40/17 square
3: Willing to make the front fit, don't wan't to go nuts and crack my fender paint
4: see above

View attachment 133245
most 255 have a tread width of 9" you'd want to run a min of 9.5" rim width for optimal cornering performance. in order to squeeze a 9.5, it's gonna have to be at least flow formed, a cast will have the inside lip too thick and it wont clear the upper spindle.

i ended up going 245/40 (235/40 was out of stock 8.6 vs 8.7 thread width optimal is minus .5" from rim width) on 17x9 +35 wheels... those are flow formed and have about 5mm clearance of the upper spindle.

good luck!

Sent from my Pixel 3 XL using Tapatalk
 

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most 255 have a tread width of 9" you'd want to run a min of 9.5" rim width for optimal cornering performance. in order to squeeze a 9.5, it's gonna have to be at least flow formed, a cast will have the inside lip too thick and it wont clear the upper spindle.

i ended up going 245/40 (235/40 was out of stock 8.6 vs 8.7 thread width optimal is minus .5" from rim width) on 17x9 +35 wheels... those are flow formed and have about 5mm clearance of the upper spindle.

good luck!

Sent from my Pixel 3 XL using Tapatalk
Thanks for the info. I'm mainly looking to run a 255 width tire for more heat capacity. Here in Texas on a hot day my current 225 tires get overheated after about 10 min of lapping. More aggressive tires and more rubber should help that.
 

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Thanks for the info. I'm mainly looking to run a 255 width tire for more heat capacity. Here in Texas on a hot day my current 225 tires get overheated after about 10 min of lapping. More aggressive tires and more rubber should help that.
255 from brand to brand can be different and even within brands can be inconsistent. the thread width is a better measure. and thread width should be .5" narrower than the wheel's width. so 9 wide, you should get a thread width of 8.5 it could be a 225 or a 265 it all depends on the brand. good luck man! jumping from 215 to 245 (same tire) it definitely maintains the heat better

Sent from my Pixel 3 XL using Tapatalk
 
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