Only rev's to 3k..HELP!!

OK heres the situation...My buddy picked up a convertible 94' GT with a supercharger which brand im not sure..I am going to give you guys a quick rundown of his mods all of which im not positive..Some type of supercharger, Edelbrock upper and lower intake manifold, BBk throttle body, cold air intake, BBK high flow fuel pump, BBK adj. FPR, MSD distributor, maybe headers but mid-pipe and mufflers for sure...OK he said it started doing this at 5k and has gradually made its way down to 3k..Basicly it WILL NOT go past 3k..I havent driven it but i rode inside..It will wind to 3k and fall on its face. Also apparently it will rev out fine in nuetral but not when it's in gear. I thought it was a mass air problem or fuel..What's all of your take on this?

(When he started it last night when he left my house it was very hesitant to start, Leading me to believe it was a fuel issue)

Thanks a lot..

Kris.