I am looking for a new set of wheels for my 96 Z28. I was reading the FAQ thread but I couldn't find the answer I was looking for. So here goes I apologize if the question has been asked a million times.

What is the least amount of back spacing I can run with out rubbing over bumps? I am looking for 17x9 wheels. I am looking for a more muscle car look, but every thing I like has a back spacing of around 4.5". Will this work with out rubbing?

 

You want +35mm offset, or 6.38" back spacing.

 

No, They wont.....They will stick out of your fenders........15x8's are suppose to have 5.5" of backspacing 15x10's are suppose to have 7" of backspacing so you would want to be in the middle of that........ I would assume that Bluez28 is correct. My 18x10's have over 8" of backspacing(58mm)

 

Consider this.... the stock 8" wide wheels have a 6-5/8" backspace. The stock 9" wide wheels (SS/WS6) have a backspace of slightly under 7.0". Think what a stock SS/WS6 wheel would look like if you moved it 2.5" further toward the outside of the fender. That's where a 9" wheel with a 4.5" backspace would sit.

As noted above... 6.38" - 6.5" is probably the limit for a 9" wide wheel.

 

I found some wheels I really like but they have a 6", 6.5" or 7" back spacing. Which BS would give me the deepest dish without rubbing? I want to go with 17 x 9.5 wheels with 7" BS on the front and 6" BS on the rear. If that will work? Thinking of running 275 40 17 in front and would like to go bigger in the back. Just not sure what size yet.

 

Now you changed the game.... a 9.5" wide wheel needs more backspace than a 9.0" wide wheel. You need at least 7.0" backspace in the front. Any more than that and the tire is going to rub on the inner plastic fender liner when the steering approached full lock. In the back, 6.0 is a shade too small. The tire will be 1/4 - 1/2" outside the fender.

If you fix the outside edge of the wheel at the outer edge of the fender, as the wheel gets wider, all the added width has to be added at the back. And, the deeper the "dish", the further the outside edge of the wheel moves toward the outer edge of the fender, or even outside the fender.

This is a 17x9.5" wide wheel with a 7.18" backspace (front and back). I personally wouldn't want the edge of the tire any further out from the fender, in the front. Going with a 6" BS in the back would move the tires out more than 1", again, outside the fender.



The fronts (17x9.5) in this picture have a 7.41" backspace. Also look at the backs. While they are 17x11, the outside edge of a 17x9.5" wide wheel with 6" BS will sit 1/2" further out, and that's outside the fender:

 

Okay, I found some wheels I am going to go with. I wanted to clear the wheel specs with you guys just to be sure that they will fit.

Size Bolt Pattern (mm) Offset (mm) Weight (lbs)
17" x 9" 5/114.3 & 5/120.7 35 25

Thanks for the help but more importantly the patience.

 

You need the 5 X 120.7mm bolt circle (actually 120.65, but they rounded up).

35mm offset on a 9" wide wheel will put the wheels about 1/4" further out toward the edge of the fender, than the wheels shown in the top photo in my previous post.