I just remembered when I put my turbo kit on I didn't put a gasket between the turbo and downpipe its a t3 pte ball bearing 61 5 bolt flange. How demanding is this gasket?

 

I was also going to add the wastegate is of course on the manifold, I guess the only thing it could hurt if it is leaking is my a/f readings? I am just curious if a leak at that section would cause any loss in power?

 

you do not need a gasket here same as on the 4 bolts its a machined serface as long as you have good flanges ne leaks!