The /6ers seem to like the Erson cam. With that much duration, I'd think power would come on somewhere past 2000 rpm. Comp Cams makes a pair for the solid lifter /6. The 252S makes power from 800-4500 rpm, and the 264S that makes power from 1200-5000 rpm. The lift on these cams is .435 and .440 respectively.
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