Edelbrock PN 7561-CP Air-Gap RPM Oval Port intake manifold is designed for high performance 396-502 c.i.d. Chevy V8's with large oval-port cylinder heads (1975 and earlier) or Edelbrock Performer/Performer RPM heads. This RPM Air-Gap incorporates the same race-winning technology that's been used on our Victor Series competition intakes for decades. The Air-Gap design features an open air space that separates the runners from the hot engine oil resulting in a cooler, denser charge for more power. Includes rear water outlets, two distributor clamp locations and nitrous bosses. Accepts all late model alternator and A/C brackets for the street. For square bore carburetors only. Will not fit under stock hood of Corvette, 1964-67 Chevelle or 1967-81 Camaro. Use with electric or manual choke carburetors sized for 750-850 cfm. This PN 7561-CP version comes with a brilliant Chrome plasma finish that is durable and easy to maintain.