As most people do I'm upgrading part by part and trying to decide between a new manifold or a o2 housing. I am keeping the stock turbo for now because I'm only looking to get 400+ whp. So far I have tbe, licp with short route (custom to keep the regular battery size) stage one cams,1120 cc injectors, walbro fuel pump, 25psi wga, and e85... If you have advice please give some... Thanks

 

I'd send the stock exhaust manifold off to buschur to be ported and coated that's the best bang for your buck and also jut have the stock o2 housing ported. In terms of gains there is not going to be much from an o2 housing.

 

So a tubular one won't really give anything more than a ported stocker? I was told I would pick up like 10-20 whp from a o2 housing

 

I have an ar design hood dump o2 housing and it didn't feel like their was a gain of that much by any means. But in the long run porting the stocker will cost less then buying a new one from someone like map since especially it is a ported stocker.
Also a ported stocker has been shown on multiple Dyno pulls to make maybe a bit less then a tubular manifold however a rock ported is around 269 bucks vs 800+ for a tubular. Unless your looking to go with. T3 turbo setup in which case you'll need an aftermarket one.

 

When I do upgrade the turbo I was going to go with a fp red. From my understanding the stock manifold will work but others will help spool better

 

You may be a good canidate for the new FP cast exhaust manifold. I'm curious to see what kind of gains there are on a stock turbo.

 

That will depend on the size of the runners

 

May I please ask? whats the o2 housing and its connection to the exhaust manifold? sorry for the very newbie question.