Is porting the O2 housing, exhaust manifold, and hotside basic enough for a good machine shop to handle or is it necessary to send it to shops who do tons of these specific parts? In the case of the latter, Buschur and PPI are the only ones I know of offering these services. Are there any more out there? Also those who have had it done, what is the turn around time and were you pleased with the porting?

 

Ppi

 

Any machine shop could do it. Not knocking My buddy Sparky, but any machine shop can gasket match a flange. It really doesn't take the expertise of a Evo specialty shop. It's not like they flow bench every ported manifold for verified results.

 

Either send it to a shop with Evo experience, such as, Buschur Racing or PPI...or DIY. Don't take it to a general machine shop or a run of the mill automotive machine shop. JMO.