Have a 63 dodge with stock wheelhouses and curious what size slicks to run. Have 15x8 steels to mount on. Running a stock width Dana 60 with factory perches.

I don't know what will actually fit, but as long as it does, it's best to go with a rim that's the same width or an inch wider than the tire you're using. Some have gone wider. But this allows more air pressure to be run while maintaining a full contact patch. The higher pressure also helps maintain a stiffer sidewall (longer life) and helps keep the car stable at speed. Many Stock class racers use 10" rims with their 9" slicks. Pressures range from low teens through the 20's (Lots of variables.) You'll need to experiment to find what your car likes.

Since you already have the rims, the offset may limit how wide you can go. Taller slicks with more gear will work better too.

I run 30 x 9 Hoosier radial slicks on my 63 Sport Fury on my 8" wheels and have also run them on 7" wheels. It runs and hooks the same on either wheel as with the 8" wheels the tires rub up inside the 1/4 panel on the street when hitting bumbs as thats why I ran the 7" since they set the tire in a little more and it fits better in the stock wheelwell. I know most say run a 9" wheel on a 9" tire but these have worked fine for me. Ron

A 9" slick is going to fit an 8" rim pretty well. Going to a 10.5 will give a lot of bulge, and you may not get any more usable contact patch than with a 9".

I run 28x9's on 15x8 rims with 4-1/2" bs, they fit in the stock wheelwells of my 67, so they'll fit into anything!

depends on how much power you have. a 9" would work fine, you probably could get a 10" if you needed it.

Thanks guys 👍

At the track, we run a 30x9" slick on a 15x8 wheel w/ 4.5" backspace. Springs are in the stock location with a '68-69 B-body Dana.

On the street, 285/70 BFG Radial T/As on a 15x7 Torque Thrusts. It helps tame down the 4.56s.