recently purchased an 87 turbo, looking to fatten the exhaust. does anyone know of any websites detailing exhaust mods for the supra. has anyone cut the catalytic converters out of theirs? what kind of hp boost did you see? thanks

any turbo vehicle will benifit HUGELY from a free flowing exhaust.. The stock exhaust is very restrictive and brings a lot of heat into the engine bay.. not sure on actual numbers, but you will notice a huge difference in spool up time and top end with a 3" exhaust
As for mods, the bigger the better.. Some guys are even running 4" and up systems on their cars..

http://www.bicperformance.com/products.htm

His name is randy, he makes these parts himself.. His downpipes are the best ive ever seen, and used, because they replace your stock turbo elbow (worst part of the exhaust) and they're a full 3".. very reasonably priced too.. Its a direct bolt on..

he's also got 3" test pipes that will bolt on in place of your catylitic converter.., After that, get a 3" Cat back exhaust.. what ever brand name you prefer..