What is the widest 15 inch tire andwheel combo for 1964 gto without any modifications?

The widest tire and wheel combo for a 1964 GTO without modifications is typically a 15x7-inch wheel paired with a 225/70R15 tire. This size generally fits well within the wheel wells without any rubbing or clearance issues. However, some enthusiasts may opt for a 15x8-inch wheel with a 235/60R15 tire for a slightly wider stance, but it's crucial to check for any potential clearance problems depending on the specific suspension setup. Always ensure that the tire profile maintains proper fitment for optimal performance.