I like all of the above suggestions. The vortec heads with the reworked springs offer the best performance for the dollar. With 9.5:1 compression and comp cams, or equivalent, 270/280 cam, you should get to your 400hp range. You dont need anything bigger than a 650 carb.

 

lol im pushin way more than that on a cast crank. I dont like steel they dont give any they just snap.

 

if you think so

cast is more brittle

 

Agreed In most cases anyway