Edelbrock 21164 Performer Vortec EnduraShine Intake Manifold Used for street rods, engine swap market utilizing 262-400 C.I.D. or industrial applications Has provisions for external water bypass Improves torque over a wide RPM range, especially off-idle through 5,500 RPM and accepts both square-bore and spread-bore carburetors Accepts late model waterneck, alternator, HEI and air conditioning Intended for later cast iron Vortec heads, or Edelbrock's E-Tec aluminum heads