C5's have good fuel system stock. If you go H/C package and want to keep it simple you just need to upgrade injectors to 30#'s and run a small dry shot to get 500rwhp. If you want 500rwhp all the time I would go with a nice supercharger combo and a mild cam and you will have 550rwhp plus all the time. Also things depend on which C5 you are going to get. A coupe weighs more than FRC's and convertibles. I know.. I said convertibles, but you will find the convertibles are less than the coupes by like 30 to 40lbs because less metal and glass. Now if you go with a supercharger you will need to upgrade the fuel system to a Racetronix fuel system with a Kenne Bell Boost a pump which is only 550 bucks. The only supercharger system I would purchase is A&A Corvettes in California.