im going to get some fast five wheels from summit and i want to know what back space i need to fit 15 x 10 out back and 15x4 out front
and one more question whats the biggest tire i can fit out back with out doing little to no mod to car

 

I have those same wheels. 15x4 only come with 1.75 backspace. My rears are 15x8's with 5.5 backspace with 275/60-15's. I have no rub on the outer fender lip. The only mod I did was beat in the seat belt pocket (thats the lower front bottom of the inner fender) I had to remove the belt recoil to remove the insulation behind it and cut the plastic flap off the back of it. Then I reinstalled the recoil so it would work properly. You may have to do this if you want to use the belts. 15x10's with 6.5 backspace will work but you will need more mods. The bump stops will need to be cut off.

 

You will need a 15x10 in a 6.5 backspacing to tuck nicely. And your not going to get a 15x10 to fit unless you mod and cut the inner wheel well. The tire size will detetmine how much you have to cut and mod also.
The 15x4 is 1.75 as 86sc5 stated.

 

I will ***** out some pics. 15x10 6.5 bs and a 275/60/15 tire in the pics.

 

94 z28 what you do to make them fit?
and im not using stock seat belts at all so im good there.
one more thing what you guys thin sould i stick with the 15x10 or go down to 15 x8

 

This is what I had to do to make them fit.
https://www.thirdgen.org/forums/whee...get-15x10.html
And I didnt have to do anything with the seat belts. It really just personal prefrence. You can go 15x8 if all your looking for is a 275 tire to put on, 15x8 might be the right way. I went for the 15x10 becuase of the better tire options.

 

so is 275/60/15 the biggest tire you can fit in a 15x8 fast five rim?
or what youguys think waitting for some help before i order my wheels

 

You can put on a 295/50/15. There wider then the 275 but there also shorter then the 275 .

 

My 275's are about a half inch from my lower control arms and about the same at my lower front inner fender on 8" with 5.5 bs. They were touching my inner fender until I used my BFH. My opinion on the 295's would be on a 10" rim. If I put 295's on my 8" I would have to do a little more beating and possibly move my LCA's in some.

 

Do you have any pictures from the rear?

 

no sorry