RPM Air-Gap 302 Intake Manifold ED7521RPM Air Gap 302 Intake ManifoldFord 289 302W, 1500 6500 rpm ED7521 7521 Designed for street 289 302W Ford, the RPM Air Gap incorporates the same race winning technology that's been used on our 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. Includes nitrous bosses. No provision for exhaust heated chokes and