differences in 243 and 799 heads?

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Dec 23, 2009 | 08:37 PM

jconk

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From: Rocklin, CA

differences in 243 and 799 heads?

i know they're cast in different factorys, are there any other differences?

Dec 24, 2009 | 10:08 AM

nightmare23

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NOPE... exactly the same

Dec 24, 2009 | 10:50 AM

JS01

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From: Odessa, Texas

Quote:

Originally Posted by nightmare23

NOPE... exactly the same

The 799 castings are a little rougher. If you are going to port them it doesn't matter though.

Dec 24, 2009 | 11:12 AM

Build #1

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From: Knoxville, TN

I wonder if my wife would notice if I stole her 799s on her Yukon and swaped them with my 853s .............lol

Dec 24, 2009 | 11:52 AM

RJB01camaross

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From: Largo,FL

The 243's have sodium filled valves, which make them a little better than the 799's.

Dec 24, 2009 | 12:50 PM

Patrick G

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From: Victoria, TX

Quote:

Originally Posted by RJB01camaross

The 243's have sodium filled valves, which make them a little better than the 799's.

That's true for LS6 heads, but the 243s that come on the 5.3L motors have solid valves. I dynoed a set of 799 heads on a 346 for a guy who swapped out his older 853s. He had a large aftermarket cam and it was tuned both before and after. He only gained around 15 rwhp which is disappointing because we always get 20-25rwhp gain with 243 head swaps. I am not convinced that the 799 heads make the same power as the 243s (even if they're supposed to be the same casting). Need more swaps to convince me that they're just as good.

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Dec 24, 2009 | 01:05 PM

Build #1

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From: Knoxville, TN

This is very intresting considering so many people have said they are the same, I thought that I read a Vette guy found a 243 on one side and a 799 on the other. What gives?