Edelbrock Air-Gap Dual-Quad Manifolds feature an award-winning design that incorporates the same race-winning technology that's been used in the Victor Series competition intakes for years. 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. RPM Air-Gap manifolds are modeled after Performer RPM intakes for high performance street power from 1500-to-6500 rpm.