2G Manifold wastegate and o2 housing

[Aakhan715]

If I have and external waste gate on my manifold, can I use stock o2 housing or does the top hole of the o2 housing need to be blocked off leaving only bottom exhaust hole open on o2 housing?

 

[Vegas Smith]

I don't think you can you use the stock hole anymore. You would have to weld it shut so that you can build boost. Otherwise, all your exhaust will bypass your turbo out your stock wastegate hole.

 

[pauleyman]

A manifold mounted gate requires you to leave the flapper in the stock turbine housing shut 100% of the time. Most people weld it shut.

 

[PlanZero]

If you already have an external WG the flapper should be welded shut, if that's the case then a stock housing would work.

 

[Aakhan715]

A manifold mounted gate requires you to leave the flapper in the stock turbine housing shut 100% of the time. Most people weld it shut.

I have a hx35 with bep housing, really don't want to weld that just in case I switch back to a o2 wastegate, what other options do I have? Can I weld shut the o2 housing gate hole, so a plate will just cap off the turbine housing. Will I get a boost leak going that route?

 

[pauleyman]

BLock off the wastegate hole in some fashion. Boost leaks are on the intake side not the exhaust side. I don't see why you couldn't block off the o2 housing.

 

[PlanZero]

There's a few aftermarket tubular 02 housings that have a flat flange where the tube normally is