Spectre Universal LS Engine Swap Plenum Kits were designed to fit your classic muscle car where space in the front of the engine bay is limited. Over the top design mounts the plenum over the top of the intake manifold and draws air in from the back of the engine compartment. These kits requires 4.25" minimum clearance between the throttle body and the fan or radiator in front of the engine and 7.25" minimum from centerline of the throttle body to the underside of the hood. The bottom of the plenums included 6mm threaded support holes to add brackets (not included).