going to give the car a tune up this weekend with a friend and ordering parts right now? Is there a difference between spark plugs? LOL there are soooo many different plugs? Its for a 2002 C5. THX

You should get some interesting responses, but I'm thinking that if you haven't done much to your car, then it's worth getting the stock ACDelco plugs. You can spend a lot more money on fancy tips and such, but these cars are so efficent already, unless you're pumping air (supercharger or cam, or headers, etc), it's just not going to matter much. Any spark plug gain would be a VERY small return on the investment.

I have Bosch in mine :D