rattle under 2001 z28

I just bought a 2001 Z28 a couple of weeks ago. When I shift then start to speed up I get a rattling sound. It sounds like it come from underneath my pedals. Any idea what it could be! Thanks for any assistance. I have a 6spd.

Might want to mention the type of trans you have. Since you mentioned "petals" (pedals), can we assume its an M6?

I'll move this to "General 67-02 F-Body Tech", since its not really an Advanced Tech topic.