I heard that porting and polishing your cyllinders and head is the best bang for your buck. A shop should do it for $500 or less.. It's the process of removing imperfections from mass produced parts and ballancing the flow of air between your intake and your manifold, then polishing to remove and reduce the recurrance of carbon build up which also impedes air flow. I hear that it can give huge gains since it opens up air flow (some cars get VERY nice like 30hp, it depends on the quality of production of the parts, hondas get 10-15hp can't find anything on toyota) also depends on the age of your engine (older=better gain because it will have more carbon build up in there).
Only problem is finding a TRUSTED shop, because it's all interior parts they can take you for a ride and say they did the 3-4 hours of work without ACTUALLY doing anything.. so be careful.. Most people try to find someone who has done it to help them, it isn't supposed to be hard. I am working on finding someone to help me do it when my new header gets here.
[ 04-15-2003, 11:18 PM: Message edited by: FX-MAN ]