I was thinking about selling a 454 that I've had in storage for some time and I should run the #'s to see what I have, but I can't find the info of what it came out of.

Looks like a 1972 block (the date cast code has a 72 in it- i'll post those later if needed.) 3999289
and the heads have a 72 in their date cast also 353049
the intake manifold # 353015

http://i127.photobucket.com/albums/p148/Camarofiend/454castingnumbers.jpg

The front pad stamp suffix of CWL is for 1973 454 Impala 215hp LS-4 TH400 4-brl.
353049 heads 454 70-73 2.06/1.77 113cc Oval port
353015 intake 454 73 Q-jet Oval port
More than likely it is a two bolt main block with a cast crank, the early 70s blocks have a high nickle content creating a strong casting. very desirable for drag racing applications but most racers will splay the block with four bolt main caps.

Thanks!