I just recently put underdrive pulleys and 10% sc pulley and a 3/4 top on my 92 sc. it also has a 73mm mass air. everything else is stock other than flowmaster exhaust system and k&n panel filter. The problem is that the car is just a dog untill it gets pushing boost. i converted my car from auto to 5speed and thought maybe the eec was the prob. so i put the one in from my 89 donor car but it just ran horrible and blew black smoke??? so i put my stock on back in? i dont know if its just too much air and not enough fuel?