243/799 heads on same motor

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Jan 31, 2018 | 10:17 PM

PapaSal

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243/799 heads on same motor

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

Feb 1, 2018 | 12:05 AM

LLLosingit

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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.

Feb 1, 2018 | 09:29 AM

01ssreda4

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Yes Ive know people who had it like that.

Feb 3, 2018 | 07:00 PM

qweedqwag

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

Feb 12, 2018 | 12:54 AM

BeatonZ06

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

Feb 16, 2018 | 09:56 PM

rednari2

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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.

Feb 16, 2018 | 10:48 PM

G Atsma

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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.

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Feb 18, 2018 | 06:08 PM

Jimbo1367

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Quote:

Originally Posted by G Atsma

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?

Feb 18, 2018 | 07:04 PM

#10

LLLosingit

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Quote:

Originally Posted by 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?

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.

Feb 18, 2018 | 09:00 PM

#11

G Atsma

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From: Central Cal.

Quote:

Originally Posted by LLLosingit

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.

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