Dr. Doom

Hi all, I've searched for a while and I could not find an answer.

I have a spare set of 15x7 wheels with 0 offset (looks like 4"bs) steelies. I know that theres been major debate on running 33x12.50s on 15x7" wheels. Well these would be a trail set and rarely driven on the street. I know that you have to watch tire pressure for wear etc..

My question is does anyone have experience running this wheel/tire combo? And will they rub?

The wheels I have on now are aluminum 15x8 centerline telstars w/ 4.5 bs. Should I just run the 33x12.50s on this set of rims?

Xj88

Its more practical to run em on the 8 inch wide rim...but they will fit on the 7. They will buldge a tad with the 7s but if its just a trail rig then the 7 will be fine...and you'll be able to air way down with the 7

XJ Stryker

Wouldnt u have to worry about coming off the rim aired down on 7's with that wide of a tire?

hankthetank

It's actually harder to pop a bead on a narrower rim cause there is so much extra rubber sticking out...I wanna try 35's on 15x7's.

Big David

My dads XJ had a this setup.It was drove in the woods but not really wheeled.I don't think it scrubbed when turning lock to lock but if it did you can use a washer to space the steering stops out alittle.

My theory behind running low pressure with the 7 in. wide wheels is the tire is so wide that they naturally want to spring outward.The little air pressure is really multiplied by the narrow wheel. That's my guess anyway.

Dr. Doom

The problem I'm having is figuring
out I'd the tires will rub on full lock. I know my 15x8 will
rub with the 12.50s because of the 4.5"bs. So I'm
wondering if the 15x7 with 4"bs will. Thanks for the replies fellas

Rock Toy

If your 12.50s are actually 12.5 running the 8 inch rim with 4.5 inch back spacing your tires inside edge will be 7.03 inches inboard of the WMS.
If you run the same tire on a 7 inch rim with a 4 inch back space the edge will be 7.14 inches inboard of the WMS.
Hope this answers your question.

Dr. Doom

ok so more rub with the 7 inchers I'm guessing even more rub when aired down and tire bulges more huh

thanks guys

hankthetank

How do you figure that? If the rim is narrower it pulls the bead inwards, bringing more sidewall with it...

mallkrawler21

7 inchers will rub on the inside at full lock

mr white

It depends on the backspacing/offset, not how wide the wheel is...

hankthetank

I see, the half inch is the kicker...

Rock Toy

The way to figure it is to divide the center section width of the tire as in 12.5 by the rim width 8 = 1.56 inches of tire for each inch of rim. Then multiply this by the back spacing and it gives you the amount of tire inboard of the WMS. 4.5 x 1.56 = 7.02 inches.
The 7 inch rim is 12.5 divided by 7 = 1.78 x 4 = 7.12 inches inboard of the WMS.

hankthetank

Ya I understand the proportion, I just skipped the half inch...