What backspace? Custom wheels being built - 88 Cutty

[CuttyBang]

Whats up guys! I'm getting some wheels built for the Cutty. I want to run a 15x8 wheel in the rear and a 15x6 wheel in the front. What backspace should i run? i read 4", i read 4.5" for the 15x8 in the rear. Which one is it? I'm planning on running a 275/60/15 tire in the rear without rubbing if possible. What backspace should i go with on the 15x6 wheel for the front? I currently have Eibach lowering springs. I read thru the 26 pages of the Wheel Fitment Guide thread and I'm still unsure : /

Any info, pics, or experience will be greatly appreciated, Thanks!

 

[lilbowtie]

3 1/2 rear on my Regal, can't remember front - need any pic's or measurements let me know.

 

[-83MONTESS-]

3.5"-4" for the rear on an 8" wheel is the best fitting and looking IMO. The fronts with that thin of a wheel I would try to do 3.5" or 4" as well. Anything more I feel would stick the front wheel in too far and not look good.

 

[pontiacgp]

have you checked the condition of the body bushings to make sure the body hasn't shifted?

 

[CuttyBang]

3.5"-4" for the rear on an 8" wheel is the best fitting and looking IMO. The fronts with that thin of a wheel I would try to do 3.5" or 4" as well. Anything more I feel would stick the front wheel in too far and not look good.

I think I'm gonna try 15x8 4"bs for the rear and 15x6 3.5"bs for the front. Thanks for all the input and advice!!

 

[CuttyBang]

have you checked the condition of the body bushings to make sure the body hasn't shifted?

nah i havent, I will look into that, thanks!

 

[403Olds]

I've got 15X8 with 4.5" backspacing on the rear and 15X7 with 4.5" backspacing and have to use 1/4" spacer's in the front on an 85Cutlass.

 

[pontiacgp]

I helped a friend figure out what BS he needed in the rear. I took a laser pointer and put that on the drum pointing up.. Measured the distance from the inside wheel well to the lip on the fender. Noted where the laser light hit the measuring tape and then figured out what BS was needed to put the tire right in the middle of the opening. I measured both sides to make sure the body was centered and the rear end was centered.

 

[lilbowtie]

I think I'm gonna try 15x8 4"bs for the rear and 15x6 3.5"bs for the front. Thanks for all the input and advice!!

Do a little double checking before you buy anything - with my 3.5 back spacing I have about 2 inches rim clearance to the frame, a 4.0 back space will leave me 1.5 inches. A 275-60-15 has a center section of 11.4 in or 1.7 in wider than the rim on both sides. With a 4.0 back space and a 275-60-15 tire it would hit the frame on mine.