These thick wall cast stainless steel swept runner manifolds are the same ones we use in our TWIN turbo kits. Manifolds are plenty strong to hold up even to the most demanding conditions. Runners are swept and opened up into the plenum to maximize the flow from each runner. Provisions for a 2 bolt waste gate are built right into the front side of the manifolds. This is the last point before the turbo. The T4 turbo mounts are a TRUE T4 opening, not a T4 flange with a 2.5" hole cut into it. This maximizes the flow leaving the manifold, by getting rid of any transition inside the manifold. The T4 flanges are drilled and tapped for studs. Originally designed to fit 1999 and up GM trucks, they may be used in other applications. Fits LS style heads. Manifolds comes with studs,nuts for the turbos mounts, a block off plate and gasket for the passenger side manifold inlet.
Wanting to build your own TWIN turbo kit. These manifolds are a HUGE part of the puzzle and now they both are CASTED. These were designed on an 2004 2x4 RCSB.