Designed for 1970 - 91 304 - 401 c.i.d. and 1967 - 69 290 - 390 c.i.d. V8's, RPM Air - Gaps incorporate the same race - winning technology as our Victor Series competition intakes. The air - gap design features an open air space that separates the runners from the hot engine oil for a cooler, denser charge and more power. For square - bore carbs. Includes standard oil fill and PCV provisions as well as early air conditioning support bracket accessory bosses. No provision for exhaust - heated chokes. No exhaust crossover. Carburetor Recommendations Edelbrock Thunder Series AVS or Performer Series carb, 600 - 800 cfm Installation Notes Recommended intake gasket 7213 or Fel - Pro MS96011. 7531 must use factory style metal valley tray. 7531 has two center bolt holes offset. Manifold height A - 4.45, B - 5.77 Carb pad height 5.11 . Port exit dimensions 1.04 x 2.10. Bracket 8034 required for 1979 and later vehicles. Camshaft Recommendations Performer RPM 7132.