Back spacing help with 15x10 Race Stars on IRS

[MalcolmV8]

I've seen two cars with 15x10 rims and 325/50/15 MT tires now and yes there is bulge but it looks good. I saw another set with 275s and they almost looked to small for the rim.

 

[ctgreddy]

Malcolm the 6.25 backspace will stick the wheel out further. So could in some way help slightly with what it hits. With irs the 6.25 should fit pretty flush with the fender. However I think a 325/50 will have some rubbing issues if you're low at all. That's a big tire, almost an inch wider than a normal 315 and 28" tall. I tried fitting a 325/45/17(almost identical dimensions to a 325/50/15) on my car last spring and gave up after constant rubbing. My cars sra tho, irs does sit in a little further and that might have cured my issue.

If you just want a drag radial, get the 275/60 radial pro. They look sweet, fill the wheel wells great and work. There's a reason all the radial records are being set on the pro's.

My car with a 15x10 7" backspacing(tucked in) and 275/60 pro's.

Not the best picture to show tires but this is a 295/55/15 et street and it was a HUGE difference between these and the pro's. Both tires were used when I got them and the 295's were pretty old so that may have a bit to do with the difference but I'd never consider a regular et street after trying them both out.

 

[04cobra88]

What was the back spacing on your 17 inch rim you tried the 325 /45 on ?

 

[MalcolmV8]

My car is lowered a little, nothing crazy. I need to take some measurements off someone else's car and measure up and see what I think.

 

[ctgreddy]

What was the back spacing on your 17 inch rim you tried the 325 /45 on ?

6.3 I believe on a 17x10 xxr. This is the only picture I have of that setup because I didn't have it long at all. Both sides rubbed on the fenders even after rolling them.

 

[04cobra88]

They look good though lol, your car was pretty low there too which springs ?

 

[ctgreddy]

Mines not that low, 28" tires just make the rear look lower. At the time of that last pic I had h&r super race springs. Currently I have stock gt springs cut aprox 1 coil.

 

[04cobra88]

Ok just checking I'm doing a sra swap no and was going to add stock gt springs not sure if u wanted to cut them yet or leave then stock running 28 inch slicks and wanted to try bot have a massive fender gap with street tires..

Sorry for using your thread to ask questions malcom!

 

[MalcolmV8]

No worries, I'm just pondering backspacing lol.

 

[wile e coyote]

No worries, I'm just pondering backspacing lol.

I'm running 15x10 billet specialties with 6.5 BS. MM brake lines, MM rear tie rods, low profile IRS bolts, and the normal grinding on the IRS knuckle. Otherwise they fit fine........and the 295/55/15's don't ever scrub unless I absolutely bottom out the IRS

 

[MalcolmV8]

I'm running 15x10 billet specialties with 6.5 BS. MM brake lines, MM rear tie rods, low profile IRS bolts, and the normal grinding on the IRS knuckle. Otherwise they fit fine........and the 295/55/15's don't ever scrub unless I absolutely bottom out the IRS

Thanks man :beer:

 

[MalcolmV8]

I've been meaning to update this thread. Ever since installing the 15x10s in the rear I get an ABS light on the dash within 1/4 mile or so of driving off. I assume it's due to the tire diameter differences between front and rear. Is there anything I can do to fix this short of replacing the front wheels with matching diameter tires?

 

[P49Y-CY]

I don't think there is anything you can do other than remove the bulb, from what I understand it can't be programmed out.

 

[MalcolmV8]

Dang that's a bummer.

 

[trmnator]

I have 17x10 with 305/45 17. Low pro bolts, billet spacer. Withstands 5000 starts