ok, I have 15's on the rear of my car now with 75 sidewalls. I plan to put the original size(16) on the car. with 50 sides. which os better for traction and drag strips? I plan to use street tires.

I thought I could keep the 15's to use at the strip and use the 16's on the street, but I'm not sure if I will get better times with the 16's or not.

also should I get a body mount kit if I want to drag alot? My mounts are soft *** original rubber.

 

Keep the 16's with some street tires and get some slicks for the 15's. You'll have a much better selection with 15" rims.

You're not going to get better times because of the rim size. The 15" rim is just more popular. It also gives a little more sidewall which is needed for drag racing. 16+ rims have little sidewall and are designed for cornering. With a small sidewall, the tire won't roll over in corners and will stay on the pavement better.

Body mount kit? Third gens are unibody. Everything is spot welded together.

 

I think he means suspension bushings. Poly bushings are a good improvement over stock rubber. But, not a cure-all. Boxed lower control arms & track arm also help.

Sub-frame connectors are a good idea to improve general body stiffness.