Set up :

Home made manifold, externally wastegated
T3 turbine outlet, internal WG hole not welded shut
5 bolt flange for DP.

Do I need a gasket between DP flange and compressor outlet?

I’m not sure if I could loose pressure from the internal WG hole, impairing spool up.

(EDIT: typo correction)

 

Ha Ha

You're right, I'm dumb...

I mean between DP flange and turbine outlet. Self owned :1

 

i ran my car without a gasket for a litle bit. leaked like crazt but who cares

 

Just copper spray that ---- and gorilla clamp it down

 

i did the wheel bearing grease trick on my 1st turbo setup. worked great after 500 miles. leaked like crazy at 1st though

 

i dont have any gaskets, and mine doesnt leak at all.. but as someone said, as long as both surfaces are flat, there should be no problem