Backspace question

[krue]

Buddy of mine is putting 15x8 rims on front of his 86 short fleet and 15x10 on the back and doesn't know what the backspace should be. He wants to run a wider tire on back than on front.

[bigblock73]

I have 10's on the back of my truck, and I think the BS is 3.5". I can check when I get home tonight. Rear tires are just shy of being flush with the outside of the wheel well lip...perfect IMO.

[krue]

How about a pic while you're at it.

[bigblock73]

Here is one (my favorite). I have 7 inch wheels in the front.

[krue]

Not to be nitpicky, but it's hard to see the tires in that pic. On my computer anyways.

[Slammed '87]

I've been thinking about this backspacing alot lately as i just bought a new set of 15's for winter rims. I had an old set of Cragar streetstars with 8's in the front and 10's in the rear, both with 4" backspacing. I hated the backspacing because the fronts and rears would rub due to extreme lowering. Most companys only offer certain backspacing, unless you go custom, so choices are limited and every wheel is different. I wanted a nice looking but cheap chrome wheel that would bolt right up and never have to worry about any rubbing and FINALLY found them. They are Cragar/Unique super supreme wheels (series 167). The fronts are 8's with 3.625" backspacing and the rears are 10's with 4.25" backspacing. This is just enough room so no rubbing. They are a great wheel and i am really happy with them. As you can see they kinda look like a A/R torque thrust, but in chrome. They were under $200 Canadian a piece so in the U.S. they would prolly be about $150ish. A heads up for anyone interested tho, the center caps do NOT fit properly on our trucks. I was able to modify them to make them work but I didn't like them anyway and bought a set of new chrome centers with 3 bar spinners. I don't have any pics yet of the wheels on my truck but i have a photochopped pic just to show roughly how they look.

[Malo83]

These are 15x9's all the way around with a 4"BS and 275/50/R15's with no rubbing problems, I also want to go 10's on the rear and read here on some earlier post that a 10" rim with a 5"BS is ideal.

[AirMale]

If you want to lower the bed over the sidewall of the tire you need 5.5 of back space on a 10" wheel.

[krue]

He's not looking to lower more than a couple of inches at the most. Looking for a more old school pro-street kinda look.

[Slammed '87]

Originally Posted by AirMale

If you want to lower the bed over the sidewall of the tire you need 5.5 of back space on a 10" wheel.

not entirely true! I ran a 15 by 10 w/4" BS and it tucked, mind you i had to ditch my 295's and go with 265's plus a lil grinding on the inner fender lip, but they did fit and had no problems with the air bags going from side to side. I always try to go with the less amount of back spacing as needed because i prefer the deep dish look, but thats just me.