This is a reproduction of the cast iron spacer used on the passenger side between the exhaust manifold and factory H-pipe on big block Ford FE engines. It is patterned after the Ford original but has no butterfly or hardware. This spacer is for the 390 GT or 428 Police Interceptor engines and replaces the heat riser valve which is often no longer functioning or even leaking. Also available is the correct “doughnut” gasket. This piece is next to impossible to find elsewhere, so we make it right here.