PapaSal

iTrader: (1)

Has anyone seen one 243 head and one 799 head on the same 5.3 motor from the factory ?

LLLosingit

iTrader: (4)

I haven't seen it myself but people have posted pictures of engines that have had them that way from the factory, They are essentially the same head in an oem application.

01ssreda4

iTrader: (96)

Yes Ive know people who had it like that.

qweedqwag

One is sand cast and the other is investment cast, same same one is just smoother than the other.

BeatonZ06

Haven't looked closely before. But that is interesting!

rednari2

iTrader: (1)

I thought the 799s were truck heads. Truck heads usually have larger combustion chambers and therefore lower compression. Otherwise the heads are the same, with the 799s being cheaper to manufacture.

G Atsma

The 799's ARE truck heads, seeing as cathedral heads only come on trucks now, but they have the same chamber as 243's. Gen IV truck engines have higher compression than earlier ones, plus more power. As said, 243's and 799's are IDENTICAL in function.

Stampede4ever

I work with two guys, 1 has a 2011 and the other has a 2012, both trucks are 4.8s, that have 243 heads.

Stampede.

Jimbo1367

I thought the truck version was 799 but I've seen several posts on here saying its 317s are the same as 243s but with a larger chamber.

So whats the truth?

LLLosingit

iTrader: (4)

799 and 243's are identical as far as specs go but were used a different casting process. The 317's are nearly identical except they have a larger combustion chamber.

G Atsma

Boom. There ya have it. I tried...