Chevy Impala SS Forum banner

What's the widest 15" wheel/tire I can fit on my box Caprice?

37K views 24 replies 15 participants last post by  91ss 
#1 ·
What's the widest 15" wheel/tire I can fit on my box Caprice? More cornering grip wanted. Looking at some Basset DOT wheels, 15x7's or 15x8's maybe. Not sure about tires yet.
 
#3 ·
I use 15X9 rear with a 3/8" spacer needed to clear the frame, 15X8 front, all made from oem aluminum Caprice wheels cut down the middle and widened. So all have the factory offset, just widened toward the inside. Even fit on a RMS with the rear skirt with Firehawk 275/60-15's. Best handling, ride and braking combo for currently available new tires. Used to have the same wheels with Pirelli P-Zero 255/60-15 that were even better in handling and braking (not ride), but they are no longer made.
 
#7 · (Edited)
15x10 will fit 5 inch backspacing no spacer required. You may need to trim the lip to fit a big rear tire. A 295/50/15 will put a goot tire on back. I had a 295/65/15 on.
So that's a 295/60/15 on the rear in the pics? I guess I've got nothing to worry about since the biggest I'm probably going to go is a 15x8. The more backspacing you have the wider your stance correct? Or is it the other way around?
 
#8 ·
no thats a 295/65/15 tire Drag radial. Its the other way around if you have a 15x8 with 5 inch back spacing it will be tucked under. But it you have a 3 inch back it will sit farther out just becareful if you plan on lowering it order accordingly.
 
#9 ·
I run 255/55R16 on an 8" rim with 4.5" backspace on a '79 Bonneville, same design as your Caprice. Front wheelwell clearance and "fill" is perfect. In the rear you'd be safe with the same specs, but depending on your tire, you may want spacers to fill out the well.
 
#13 ·
285/40/18 on an 18x10" with a 5.5" backspace, and it tucks.
 
#16 ·
What's the widest 15" wheel/tire I can fit

Many confuse backspace,and offset. Offset is always referencing the wheel centerline either +,or- Backspacing is the distance from the inside bead to the mounting flange. The example given of a 15x10 with 5" backspace would have a "zero" offset. The mounting flange is in the center of the wheel. If there's a choice between slightly different backspace,go with the smaller. You will always be able to move tire/wheel out with a spacer,but you can't bring it in if it's out a little to far.
 
#19 ·
Many confuse backspace,and offset. Offset is always referencing the wheel centerline either +,or- Backspacing is the distance from the inside bead to the mounting flange. The example given of a 15x10 with 5" backspace would have a "zero" offset. The mounting flange is in the center of the wheel. If there's a choice between slightly different backspace,go with the smaller. You will always be able to move tire/wheel out with a spacer,but you can't bring it in if it's out a little to far.
Don't you mean "go with the larger" backspacing?
 
#20 ·
What's the widest 15" wheel/tire I can fit on my boxy

The greater the backspacing,the further in the tire/rim will be. As I mentioned before,the tire/wheel can be moved out with spacers. Most steel wheels are neutral,or close to it. I did fit a 275/60 on a 15x10,and I suspect a 295/50 would have fit also. Long story short, I meant greater. This is one reason I dislike using backspacing figures,I find offset specs much easier to use.
 
#22 ·
What's the widest 15" wheel/tire I can fit on my boxy

Rule of thumb is to stay within a inch of the rim width. You can get away with more if the sidewall is taller. A 10.5" tire is better off on a 15x10 rim,than a 15x8. But it's probably doable. I wouldn't try it on a 15x7.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top