a pretty good gain to clear out the exhaust manifolds. Do you have access to a dremel, air drill, high power drill? If so you could do most of the work yourself, or send it out. I have been porting & polishing for a while and think it's a very nice addition to any Z. The exhaust manifold is a very noticable gain. Port matching is very good once you get to the higher stages (past stage 3), so I've been told. But if you plan on going for higher HP #'s you might as well knock it out once you have the engine apart or have plans. What is the application (non turbo or turbo)????
