heres the parts i have for the new engine combo:
solid roller cam:
adv dur. 287in-300ex
@ .050 253in-265ex
lift .604/.604
lobe center 108
lash .022/.024
centerline 104

vortec heads that hav light porting but will probly get a little more.

i can build a 355,383, or 406. im thinking 383 cause the 400 block needs more work. i want about 11:1 comp. probly go with about 4000 stall and keep my 373 gears.
i ant about 475 hp NA and will probley go with 175 shot.

so given my car weights 3450 w/me and the hp/converter/gear and traction permitting what do you think i migt run. this is in a 72 chevelle. can i hit the 10 sec mark?

I don't think you'll get .600 lift with vortec heads, the max that I've seen is .525 :confused:

Vortecs have pretty small intake runners..which will limit your HP goals. They will make a ton of low end torque(being truck heads) and support 400 HP pretty well, but with a cam like that, a head with a 215cc intake runner and that flows good after .600 would be the wiser choice..JMHO

With that big of a cam and that many cubic inches, I think you need a way better head than a vortech.