Hello Lee,
I believe the information is in a April 97' issue of "Street Power",which is no longer being published by McMullen Argus. The article cover's a black 95' C36 that has been made over by Arizona's Motorsport Design owned by Bob Holcombe (of race fame). They take the ower output to 500+Hp and 550+lb-ft, I think the article quotes 561Hp to be exact! If you want I will try and scan the article and send to you or post, just let me know.

Ross N.
96' C260