So I picked up two heads that were identified as 243/799 heads, but the casting was shaved off at the corners. Just wanted to see if anyone could tell by the casting #s that I can see to verify what it is. See attached pics! Thanks!!

 

12564243 is a gm part number. Comes up as a 2001 ls6 head

 

Well! So those have sodium filled valves. In that case I am ecstatic. Ported/polished and will be going on an LQ4 soon.

 

They may not have those valves since they are have had work done to them. They could have been swapped out etc. Technically they should but only way to confirm is to take a few out and weigh them.

 

Or measure length, the lightweight LS6 valves are longer.