Well, i didn't dyno it, i just acquired it a few weeks ago, but the old man who owned it before me had it dynoed, and he said that he always ran the cheapie 87 gas, and when he dynoed it on 94 octane it went up to about 421...but of course he lost that dyno sheet...the only one i have says 410 on it. oh well, soon i will dyno it with headers w/o cats and see what kinda gain i get.
Mark, btw, it's a '99 GTS.