My buddy and I each own a 95 gt. His gt he says makes rattling noises when he steps on the gas....I asked him if it only occured during high revs and he replied affirmatively. I actually haven't heard this myself but it sounds an awful lot like engine pinging from his description...he told me he has switched to high octane gas with no improvements. So I told him to check his igniton timing.. from this description that is all I can think of causing the problem....do any of you have any better ideas?