not to rain on anyones parade, but busa throttles are too big for a b series. they gotta be about 42mm plates, with about 5 inches between plates and end of manifold. also gotta have the right size vacuum canister, or power brakes will suffer. if its homemade, it had better be EXACTLY the same length runners with PERFECTLY smooth transitions inside manifold, of your losing power left and right. Pics would be a definate make-or-break on these throttles.