Stage III Ported A1 intake manifold - Porting begins with porting the intake to Stage I ported A1 intake manifold, balanced flow between each runner then cut off the top of the plenum and port the runners and the inside of the short turn radius area.
The Stage 1 and Stage 3 intake manifolds are gasket matched to the factory gasket. The Stage 3 and Stage 1 ported intakes both fit the same stock gasket. Customers with modified cylinder heads may send a gasket template so that the manifold can be ported to match.
- Air pressure measured in inches of water for each runner. Results presented for runners Left to Right.(Runners 1-4) Lower numbers indicate more air flow.
7.5" ,7.5", 7.5", 7.5"