[98Cobra_sleeper]

i have 18x9.5 inch wheels all the way around, but i dont think i can retain the 18's with the kit. ima get it aligned before i change the wheels to see how wide i can go. i really really really wana keep my gt500 style wheels. i do not like the bullet style rims but thats the only 17x8 inch wheels that are offered around that i know of.

[JoshC!]

what kit? bullitt wheels are in a lot of diff sizes 17x8 17x9 17x10.5 and theyre also in 18s

[M.P. Cobra Fan]

These are 265s on my 9" rim. Imagine what anything smaller would look like

[98Cobra_sleeper]

i have a HP Performance twin turbo kit. I know bullets come in those sizes, i want to keep my gt500 rims, i dont want bullets but bullets are the only ones that come in a 17x8 which appears is the optimal size for clearance reasons on the TT kit.

[JoshC!]

id call hp and see what they have to say

[98Cobra_sleeper]

yeah the problem is that they almost never answer the phone and they tend to not call back or answer emails when you leave messages.

[JoshC!]

great customer service

[89StangGT]

Originally Posted by 00vert ^+1 that wouldnt matter

WRONG, it would.

Originally Posted by ReverendDexter Why would the rim diameter matter?

Because the bigger diameter of the rim, the shorter the sidewall is going to be, hence the more it will stretch. A 245 tire with a 25.5" overall diameter will fit on a 17x9 MUCH better than a 245 tire with a 25.5" diameter on a 18x9 rim. That's why you can't put 315/35/17s on a 17x9, but you can put a 315/60/15 tire on a 15x8 rim. The smaller the rim, the more sidewall you can run. Given that the OP is looking for a street setup, I'd guess to keep his ABS and wheel speed sensors happy, he is going to want to keep the same diameter of front tire as his rear, usually in the 25.5-26.0" range.

[89StangGT]

These are 245s stretched onto my 17x9s.

[ReverendDexter]

Originally Posted by 89StangGT Because the bigger diameter of the rim, the shorter the sidewall is going to be, hence the more it will stretch. A 245 tire with a 25.5" overall diameter will fit on a 17x9 MUCH better than a 245 tire with a 25.5" diameter on a 18x9 rim. That's why you can't put 315/35/17s on a 17x9, but you can put a 315/60/15 tire on a 15x8 rim. The smaller the rim, the more sidewall you can run. Given that the OP is looking for a street setup, I'd guess to keep his ABS and wheel speed sensors happy, he is going to want to keep the same diameter of front tire as his rear, usually in the 25.5-26.0" range.

Okay, but that's not how tire sizing works. Sidewall size as it's expressed in metric tire sizing is only a factor of section width, and totally independent of wheel diamter. The series number is a percentage of the width - that's why a 225/55R16 and 255/40R17 are the almost the same outside diamter - 55% of 225mm is 123.75mm, 40% of 255 is 102mm. 1 inch (the difference in rim diamters) is 25.4mm; 102+25.4 = 127.4mm, or less than a 4mm (a RCH over 1/8 inch) difference in overall tire diameter.

A 235/35 is going to have 82.25mm of sidewall (~1.6 inches per "side") whether it's on a 14" rim or a 24" rim.

[89StangGT]

Originally Posted by ReverendDexter Okay, but that's not how tire sizing works. Sidewall size as it's expressed in metric tire sizing is only a factor of section width, and totally independent of wheel diamter. The series number is a percentage of the width - that's why a 225/55R16 and 255/40R17 are the almost the same outside diamter - 55% of 225mm is 123.75mm, 40% of 255 is 102mm. 1 inch (the difference in rim diamters) is 25.4mm; 102+25.4 = 127.4mm, or less than a 4mm (a RCH over 1/8 inch) difference in overall tire diameter. A 235/35 is going to have 82.25mm of sidewall (~1.6 inches per "side") whether it's on a 14" rim or a 24" rim.

This isn't my first rodeo. I know how tire sizing works. He can use a 235/35/18 on his wheels, it's just going to be stretched.

[ReverendDexter]

Originally Posted by 89StangGT This isn't my first rodeo. I know how tire sizing works.

Okay, so where am I wrong? I can't fix the errors of my ways if you don't point 'em out.

[89StangGT]

Originally Posted by ReverendDexter Okay, so where am I wrong? I can't fix the errors of my ways if you don't point 'em out.

Read my post again. I said:

Because the bigger diameter of the rim, the shorter the sidewall is going to be, hence the more it will stretch

A 235/40/17 tire (24.5" tall) is going to have a taller sidewall than a 235/35/18 tire (again, 24.5" tall) thus causing more of a stretch with the larger rim. When your overall tire diameter is a static non-changing number, and the diameter of the rim is changing, that only leaves one thing to change about the tire..the sidewall. My post said as quoted above, with the bigger diameter of the rim, the shorter the sidewall is going to be, which is true. The shorter your sidewall, the more it will stretch, given the tires in both sizes have a 9.4" section width.

[ReverendDexter]

Originally Posted by 89StangGT A 235/40/17 tire (24.5" tall) is going to have a taller sidewall than a 235/35/18 tire (again, 24.5" tall)

Okay, I see where the miscommunication is. This is the post I was originally refuting:

Originally Posted by 89StangGT Are you using 17s or 18s? You MIGHT beable to stretch 235s on a 17x9 but no way on a 18x9

The only variable you bring up is wheel diameter, so my inference is that you would mean everything else is the same. But you're not - you're talking 235/40R17s vs 235/35R18s, so, yes, there's going to be less sidewall to stretch with the 18s.

All better now

[89StangGT]

Originally Posted by ReverendDexter Okay, I see where the miscommunication is. This is the post I was originally refuting: The only variable you bring up is wheel diameter, so my inference is that you would mean everything else is the same. But you're not - you're talking 235/40R17s vs 235/35R18s, so, yes, there's going to be less sidewall to stretch with the 18s. All better now

I was retarded in the second quote. I'm all better now.