Just curious what the difference is in these heads. Always hear about people working 243s but don't really hear much about 799s

 

They are very similar, I don't think the 799's have the sodium valves and are a little rougher and dont flow quite as well though almost as well. Sure someone else will chime in.

 

same specs as a ls6 head, no sodium valves and no stock ls6 valve springs. That is pretty much it, I run 799 heads.

 

The head castings are the same.

 

Both are very similar with only minor differences from the factory, but when working them over the process is essentially the same considering they are of the same port design.

 

If you have 243's from a 02-04 Z06 or 04-05 CTS-V they will have the hollow/soduim valves.

Any other 243 will have regular solid stem valves. I got mine off a 2010 GM 5.3 truck. This includes LS2 243's as well.

799's are a bit of a rougher casting, but that doesn't amount to a hill of beans if you're porting them.

Here's a bomb-*** set of 799's, FYI https://ls1tech.com/forums/generatio...-cnc-work.html

 

So essentially if the heads are going to be worked, there is no difference I'm assuming.. It's time to invest in some heads and I found a set local for 175$.. A I will be doing the work.

 

Thats what I was trying to say. From what I know the casting #s are the same. Differences are the parts used. Thats what I thought anyway...

 

that's a good deal at $175

 

Yeah that's a steal jump on it

 

Done picked them up.. now for a question on valve springs. The car currently has a 224/230. .589 lift cam that's been in there for probably about 6k miles. I may keep this cam and mill the heads quite a bit to bump compression.. Do you guys think it would be ok to swap these springs to the new heads or do I need new springs?? By the way, the springs are the prc set rated for .650 lift from tsp..

 

Only one way to find out.....

Get them checked at the machine shop. I doubt you've lost any pressure in 6k miles, but stranger things have happened, and there's just too many factors to consider on an individual basis for spring longevity.

You're pulling them anyway.... Just get them checked.

 

^Agreed, the springs should be in great shape but you definitely want to get them checked out since they will be coming off for the swap anyway.

 

If you have ever seen a set side by side there are subtle differences. The casting process is different. Notice the "triangle" under the spark plug holes on the 243s. I believe its called "Die Cast" as the 799s and others are sand casted.

 

The design of the heads are the same but the 799 are sand cast and the 243's are investment cast. Bought a TBSS motor that had one each. so GM don't care.

 

One type of head on each bank? lmao crazy The 243s are equipped with sodium filled valves which are lighter but id imagine both banks have the same valves, springs etc

 

[QUOTE=dr_whigham;16519961]If you have 243's from a 02-04 Z06 or 04-05 CTS-V they will have the hollow/soduim valves.

Any other 243 will have regular solid stem valves. I got mine off a 2010 GM 5.3 truck. This includes LS2 243's as well.

799's are a bit of a rougher casting, but that doesn't amount to a hill of beans if you're porting them.

READ THIS

 

This post was from 2012, Must have been searching for something?

 

Some 243 heads have the sodium filled exhaust valves and hollow stem intake valves, but not all of them. Most have solid stainless steel valves.

 

thanks for clarifying