here, so "search" to see for yourself. The I/C's will certainly help if you're going up to 13 psi. My impression is that the manifolds would help, buy would be overkill for stock turbos, given purchase plus installation costs. People will say: if you're taking the engine out for manifolds, it only makes sense to upgrade turbos at that time. So there are other ways to spend that money. The Selin dual MAF setup is getting great reviews here. If you don't have 3" expansion downpipes yet, they are an upgrade from whatever you have.