Here's why:
* Stock wheel size: 1990 Camaros typically came with 15-inch wheels, but the *width* of the stock wheels was significantly narrower than what's needed for a 275-width tire. A 275 tire is very wide. It would be far too wide for the stock Camaro rims, likely causing the tire sidewalls to bulge excessively and potentially rub against the suspension components, fenders, or body.
Even if you found a 15-inch rim that was wide enough (which would be rare), the 60 aspect ratio would likely lead to significant rubbing issues.
You need to find tires with dimensions appropriate for your stock wheels. Check the sticker on your driver's side doorjamb or your owner's manual for the recommended tire size. Using a different tire size requires careful consideration of potential clearance problems.
