I recently bought a 1997 z28 Convertible 6 speed.
Everything stock minus a V supercharger. I want to put exhaust and bigger rims on it, But i cant get a straight answer from anyone as to what will fit for tire size! I would like to put 18's on it with some wide tires and not worry about having to mod anything.......Any suggestions ? Also whats the best exhaust to go with?

 

A good place to start for tire width would be to let us know what width the wheel you have or are looking at is.

 

A set of 18x9.5" wheels, with a 56mm offset will fit with no modifications. Correct size tire would be 285/35-18.

Or if you want a wider tire in the rear, consider:

Front: 18x8.5" 45mm offset, with a 255/40-18
Rear: 18x10.5 56mm offset, with a 295/35-18

The rears may take some very minor clearancing.

As far as the exhaust, best idea would be to post that part of the question in another forum.... either "Exhaust", "Forced Induction" or "LT1 Based Engine Tech".