Going with a bigger (Ferrea)intake valve and sizing the throat at 88-90 percent would defiantly increase performance. 8 intake valves would cost about 150.00 on ebay or from one of our members. Do not get greedy on the throat sizing as it will kill the flow.

1970 Duster
Edelbrock headed 408
5.984@112.52
422 Indy headed small block
5.982@112.56 mph
9.42@138.27

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