Rear Tire clearance question
 

About how much tire clearance should I have between the fender wells? I just got some 20X9.5 rims and mocked the rims up and have 1 5/8" outer and 1 3/4" inner clearance on the rims. I am trying to figure out how big a tire wheel fit. What is a good rule of thumb? 1" or 1/2" They are going on the back of a 83 Chevy C10.

The more suspension travel and the taller the sidewall the bigger the clearance needs to be. Intended use, suspension design, and how much the tire tucks into the fender all factor in as well.

In general, my goal is 1" to the inside and 1/2" to the outside.

Your 9.5" wide wheel should measure 10.5" outside to outside. Some math tells us that you have room for about 12.5" of tire. A 305/30-20 on a 20x11 would fit comfortably in that space.

Thank you sir, I think I was on the right track, just wasn't sure. I am going to Install the Ride Tech Street Grip kit which will probably lower the truck another inch or so. It has already been lowered a bit. It will probably mostly just be street driven with an occasional auto-x thrown in for good measure. I had been thinking 295/30-20s. Thanks again for the help.