Well, not sure about your questions, but I used a set of them on a motor we built for my wife's 64 vert. Mind you, this is meant to be a cruiser, may even put 2.94 or 2.76 gears in it.
413 block bored to 4.25, 3.75 stroke, so the motor is a 426.
9.6:1 cr with ross pistons. Comp xe275hl cam, 231/237 at 50, .525 lift.
440 source heads ported by ou812/IMM. RPM intake with 770 holley street avenger vac sec carb.
Made "only" 470hp and 486 tq on the dts dyno.
440source head dyno pull