In a couple weeks I'll be doing my cam, head stud, head gasket swap and was thinking since I'll have the heads off, is there a better factory head out there for my 5.3L than the 706's? I have heard of the 706 castings having cracking issues, especially under boost.

799 heads seem affordable and flow well, and I could have them milled back to stock compression. I guess there are basically the same as 243 LS6 heads.

What about 862 heads? I guess they are the same as 706 but are they more reliable?

Some more info I've found:
https://www.performancetrucks.net/fo...i-have-496592/
http://ww2.justanswer.com/uploads/Bl...t_loss_5.3.pdf

 

If it's in your budget get the 799/243's and dont look back. I'm in the same boat as you. I will just clean up my stock 862's and bolt them back on. I'm planing on running a MPT 70 with 12#. The Castech casting were supposed to be the one's that leaked.

 

799s are definitely affordable, seen some for under $400. How much do they have to be milled to return to stock compression?

 

I think they need to be milled like 0.020-0.030" for return to stock compression. Like I wroye over on Tech, I use the 706 heads (unmilled unported) and I make decent power. I'd love to upgrade to 243/799, AFR 205, or Edelbrock's 190cc heads.

 

Ran the times in my sig with 706's.

 

706's got my 5.3 into the 11's. But if you can get a deal on some 799's, it's worth it.