i was wondering if anyone wanted to take a stab at what kind of gains ill get out of porting/polishing a stock mani, o2 housing, turbo outlet, and possibly intake mani?

i just picked up a stock ex mani o2 housing turbo and wastegate really cheap and i wanna port it all if it would be worth it with a new tune

 

IMHO, ported ext/intake mani/turbine housing get nice gains 5-15whp and the o2 housing... not worth it at all.

Get a cheap Megan o2 housing for 100 bucks or an epm for 260, the epm with more gains of course

but there's def some gains in everything but the o2.

 

not to sound dumb or anything but 5-15 whp all together or per part ?
im gonna do that and throw on a lower ic pipe and head for a tune

 

Ported Exhaust manifold yes. Ported stock o2 no. You can get cheap s.s. ones and they net better gains and look better if it matters to you. Ported intake is also very good for a daily driver along with the new skunk 2 68mm throttle body.

Porting the exhaust manifold will net hp gains and spool. The intake manifold will help with the higher rpms and hp along with the tb. Porting the turbo is also important. Making the exhaust as smooth and transitions from head to exhaust manifold and exhaust flange to turbo. Then theres porting the turbine housing inlet and outlet making them also as smooth as possible. I dont think porting is bad no matter what you plan for your car until you move to the next level and thats just pretty much a stripped track car if you got the dough.

I think anyone can port its just about taking your time and not taking out to much and tapering it in whether your gasket matching or w/e. Just a die grinder and a few different bits. Also to add make sure you dont try and make anything to do with the intake manifold smooth. It needs roughness to a certain degree for correct atomization of the air to fuel ratio.

I thinks theres plenty of info here that can say the same thing so try searching to see what you find. Im just bored and up late. lol.

 

Stock O2 housing inlet is already about 63mm. But the outlet after the WG merges with exducer out is about 56mm which is the major restriction. You can open that up safely to about 61 mm. Which is pretty danm good considering you can pick these up close to free and they keep the rest of the assy strong by bolting to the block.