Small Block Cam Info - Magnum Head Swap

no problem
You should be able to make the Lunati 700 work Ive seen two versions one is 250-206 intake and the other is 253-208 intake
as far as I know (AFIK) it's the only shelf cam that comes close

you could have Lunati grind with the 700 intake and the 701 intake ground on the exhaust giving you 253-256 @.006


You could have Engle grind the K-52 (good lobe) on the intake and a slightly longer (depending on you head flow and exhaust) exhaust from their cam library to meet ex lift

This is the best combo that comes oh so close
Jones 256 202 120 .305 .461 50% fatter @.275 than DC 260 (269 @.006) .305 lobe is only .002 above your spec

H64307-66299 256/264@.006 202/208 .307/299 .491/478 w/1.6 111 LCA IC 109 ex 114 you could have the LCA wherever so find another .007-010
you could also have Mike spec a different ex lobe to match your ex flow reuirements- actually it's better to let him pick the lobe once you nail down your needs

Crane also has some out of catalog lobes
Crane 2022880 252-4 202 113 0.299 H2 series .904 lifter (260@.004) The 252-4 is my .006 estimate
but you can see that the Jones is considerably bigger at .200

The Engle and Jones are sort of Dwell cams big noses for great wear

here's a comment on the Jones cam above
"07-20 38 10 @.050 3 0verlap per Shawn Watson
IO same stock 401 IC 5 later stock ex opens and closes 4 degrees earlier than stock

Custom Mike Jones cam, 202 max area intake lobe Jones designed for Chrysler 440s.

More area under the curve than a longer-duration cam like a Comp 268, extremely fat at 250-275 lift, about 50% more than a Mopar Performance 260 cam.

Fast acting, but the nose is big and reduces wear
Longer duration style 208 (264) exhaust lobe for high-RPM power,
Over 400TQ from 3400 to 4600 and over 375TQ from 2800 to 5000 in AMC 360.