Anyone heard of a 799 cylinder heads casting? If so, do you have the specs on it?

 

Looked through all the gen 3 casting numbers and nothing on 799

 

Super secret head from deep inside GM's performance division. Only 5 sets known to exist.








































j/k Hell I don't know but that sounded cool.

 

I remember this guy was selling a pair of heads that had the 799 number....they look like LS6 heads to me. ....he said that they were the pre-production LS6 heads made in 1999 or 2000....dont know for sure though but woudnt doubt it..they looked dead on like LS6 heads...hopes this helps point you to the right direction...

 

I've seen some odd casting number LS6 type heads that slipped out of GM, but can't remember the casting number.

 

From what I've read in the past, 799s are prototype/pre-production LS6 heads. Supposedly cast in Mexico and approximately 400 sets made. Whether they had the same components and all details of the casting identical, I don't know/doubt it...But for the mostpart, a LS6 head.

 

I've had numerous sets of these, they are early LS6 heads, everything being the same, ports and chambers. Dave

 

my 05 Z71 with L33 5.3 has 799 heads on it.

 

That being the case, it is an LS6 style head. The part #s in the GM catalogs show the LS6, LS2, L33, LH6, LS4, and ALL 2007 4.8L, and 5.3L truck motors getting this same bare head. Looks like it's going to be easier to come across LS6 castings in the near future.

For ref. the bare head part # is 12564825.

Hope this helps!!