i have a 305 TPI in my Iroc so if thats what you got you could do the stuff i did, headers, cat back, gut your air boxes which isnt a real noticable power difference but it seems to rev smoother if that makes sense, test pipe, and that will make a good bit over stock.

 

well i got a 305 tbi so ya lil differnt.
and i got the cat backdual exhaust.