porting and bore
 

hey guyz, question. how much power would i gain if i were to bore the the 4.3 .030 and port the heads? would i have to do anything else? is it worth it? feel free to state your opinion. just trying to get an idea on things.

Just think of your engine as a big air pump the more air you can put in and mix and burn correctly and then get rid of out exhaust the better the engine will run, I am a firm believer in porting and polishing as long as you dont just port too big nice boowl work and port matching heads to manifolds really wakes a engine up!!

If youre already getting all that done, you might want to throw a more aggressive cam in. With stock everything, and just a better came, you can really get some decent power gains.

Do you need a PCM tune with a new cam? Anyone?

As far as a PCM tune with a new cam, it depends on how different the profiles and lobe separation are.