FWIW, as I recall, a .333" lobe Crane could get your '70 440 engine Abody mid to high 12s with stock HP 906 heads possibly gasket matched, a fresh valve job, six pack, and FWs.
Curious, what rockers and springs are you planning for that Whip cam? Are your 906 exhaust seats hardened or stock?
With the stock "HD" rockers I recall a couple push rods blowing through 'em.
Here's that relic Crane and a P5007698 next to it....
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