Assault Racing Products PC3000 Big Block Chevy Dual Plane Oval Port Polished Aluminum Intake Idle-6000 RPM BBC RPM Range: Idle - 6000 Dual Plane Manifold Height: 5.75 in Oval Ports Dual carb bolt pattern for the spreadbore Quadrajet or squarebore Holley 4150/4160 style carburetors