I have one more of these Hilborn "Turbo Manifolds" for sale. Only about a dozen of these were ever produced so if you want something unique for your hot rod here it is. Fits a small block Chevy, has a 2-5/8" opening in the center for the throttle body, 3-1/2" bolt spacing across from each other (6 bolt pattern), and the pad is a hair over 4" OD. It is currently setup for mechanical injection but could be changed if desired. The plenum is open like a single plane. Brand new manifold and extremely rare. Last one going up for sale $750 shipped to the lower 48 states.