I am with kendallh. But I do also have an sr with stock internals and no cams putting down 392whp with a stock manifold with a gt2871r .64 on 24psi. The key as Martin from R S Enthalpy is in the external waste gate that I have had him do to it. I was like you wondering if I should do an aftermarket manifold the Megan's and others that fit the t2 flange. But like some other people have said the gains aren't worth the problems. Problems being bad quality manifold that crack. But that is just my opinion.