LS6 Heads
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Joined: Nov 2005
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From: Gainesville, GA
I'm rockin a hotcam now with 98 heads 
I am honestly going to say that I would be fine with a set of LS6 heads. Even if aftermarket heads could provide an extra 30 hp or more, I still couldnt justify dropping over a thousand bucks more on them, versus just finding a smokin deal on some LS6 heads. I'm in no hurry to buy them now anyway. Hell, you could almost sell the stock cats off your car to pay for a set of 243's 
I am honestly going to say that I would be fine with a set of LS6 heads. Even if aftermarket heads could provide an extra 30 hp or more, I still couldnt justify dropping over a thousand bucks more on them, versus just finding a smokin deal on some LS6 heads. I'm in no hurry to buy them now anyway. Hell, you could almost sell the stock cats off your car to pay for a set of 243's 
I'm rockin a hotcam now with 98 heads I am honestly going to say that I would be fine with a set of LS6 heads. Even if aftermarket heads could provide an extra 30 hp or more, I still couldnt justify dropping over a thousand bucks more on them, versus just finding a smokin deal on some LS6 heads. I'm in no hurry to buy them now anyway. Hell, you could almost sell the stock cats off your car to pay for a set of 243's
I am honestly going to say that I would be fine with a set of LS6 heads. Even if aftermarket heads could provide an extra 30 hp or more, I still couldnt justify dropping over a thousand bucks more on them, versus just finding a smokin deal on some LS6 heads. I'm in no hurry to buy them now anyway. Hell, you could almost sell the stock cats off your car to pay for a set of 243's You really could...
Now someone post pics of this visual valve difference thing the other guy is talking about, if someone does I will go pull a valve out of my Z06 heads.
I'll snap some pics of both valve types when I'm back at the shop on Tuesday.
From memory, the weights of the valves:
LS6 intake: 76g
LS1 intake: 99g
LS6 exhaust: 65g
LS1 exhaust: 89g
From memory, the weights of the valves:
LS6 intake: 76g
LS1 intake: 99g
LS6 exhaust: 65g
LS1 exhaust: 89g
no matter what the minimal difference is of the ring you would have to have both valves on hand to know! Yes there is a difference in weight, and there is a difference in length, but like i mentioned you would have to have the other valve handy. and what about the intake valves, same difference in length and weight, but everything else is the same according to your statement. so how do you really know if you have a complete set of sodium valves?????
It would be nice to see the pics of comparrison.I Have a set of 799,s out of a 05 ecsb pickup. I was told they are ls6 heads. They came on a alum. 5.3 with flattops and those heads,I think L33 engine code. They didn,t come with ls6 springs though.I,d like to compare the valves.
I have not claimed anything except that if you were to LOOK at a standard valve, you will henceforth be able to tell a sodium valve apart from it, or any other exhaust valve with a different face profile for that matter. The original question was:
"Is there a way to visually identify LS6 243 heads with the sodium valves vs the LS2 243 heads"
And the answer is yes. If all you are concerned with is telling apart a set of LS6 valves installed in a head from a set of standard LS1 valves, then the exhaust valve face profile is the biggest visual clue, and all that may entail is a casual "hey, that doesn't look like the standard LS1 valve I saw last week. . . ." If you were to tell a Camry from an Accord apart from each other, you wouldn't need them sitting next to each other to acknowledge a difference in visual appearance.
That's a much more difficult question than the OP, and one I can't really help you with. Since I haven't seen every aftermarket valve out there, I can't say whether the LS6 valves have any visual traits that distinguish them from all other valves -- I've so far only pointed out how they differ from the standard LS1 oem valves. Also, if a head is determined to be equipped with the sodium exhaust valves, it's reasonably safe to say it should have the hollow LS6 intake valves as well, hence why I haven't commented on them.
I'll get some pics of both LS1 and LS6 valves tomorrow.
"Is there a way to visually identify LS6 243 heads with the sodium valves vs the LS2 243 heads"
And the answer is yes. If all you are concerned with is telling apart a set of LS6 valves installed in a head from a set of standard LS1 valves, then the exhaust valve face profile is the biggest visual clue, and all that may entail is a casual "hey, that doesn't look like the standard LS1 valve I saw last week. . . ." If you were to tell a Camry from an Accord apart from each other, you wouldn't need them sitting next to each other to acknowledge a difference in visual appearance.
Originally Posted by regency
so how do you really know if you have a complete set of sodium valves?????
I'll get some pics of both LS1 and LS6 valves tomorrow.
Last edited by drz; Aug 18, 2008 at 12:44 PM.
ls6 or ls2 ??? I asked the same question few months back - i have a NOS set I believe LS6 heads hopefully with the lighter valves. I'm going to look at mine again later wonder if possible to measure length while assembled? id hate to have to do some disassembly just to weigh them.
Valves well heres a picture of the lightweight valves out of LS6 crate motors see the color coding is different than what my new heads have :
and heres a pic off ebay thats supposed to be off a LS2 crate motor :
its blurry but same as my head pictured above of course when they are new you can make out the paint colors - hope this helps some
and heres a pic off ebay thats supposed to be off a LS2 crate motor :
its blurry but same as my head pictured above of course when they are new you can make out the paint colors - hope this helps some
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Z06 Cts-v Ls6 Heads And Cam Hello, getting ready to swap out the Heads, Cam, Pushrods, Rockers on my 2004 CTS-V. pm me offers for everything. Heads and cam are exact same as whats in the Z06 vettes. Car only has 36,000 miles on it and runs like a wet dream. Shop should have everything ready to mail out in 3 weeks. Paypal only. Great upgrade for your LS1s. I may also sale my LS6 intake but havent decided. Send me offers on that as well.
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Sodium filled valves on the left...
2001 LS6 valve vs. 2002 LS6 valve
"The valves in the 02 LS6 are 0.6-mm. longer than the valves in all other Gen III engines."
"With the higher lift (of the 2002 LS6 cam), we needed to reduce the mass of the valvetrain or start getting into a float condition," John Juriga commented. "We went to hollow stem intake and exhaust valves, very similar to what we used in the ’96 LT4. We pushed the edge with a state-of-the-art, 0.8-mm. (valve stem) wall thickness–very thin stuff. The exhaust stems are sodium-potassium filled."
Not only are ’02 LS6 valves taller, but these cutaways, made before the valve goes through the final machining steps, tell a bigger story: the significant mass reduction in hollow stem valves. The one at center right is the exhaust valve and its cavity is filled with the Sodium-Potassium compound.
The ’01 intake weighed 99 grams but the ’02 weighs only 76. The ’01 exhaust weighed 86 grams but the ’02 exhaust weighs 63 grams. The exhaust stems are filled with a 78% potassium/22% sodium mix to help cool the valve. "NaK" is unstable and may spontaneously combust when exposed to air with 50% or higher humidity. Do not cut open or shorten 02 Z06 exhaust valve stems.
Jim Hicks stated, "without the lightweight, hollow-stem valves, you loose about 300-400 rpm in limiting speed. You’re gonna be running into some significant valve train distress at 6200-6300 rpm.
"The valves in the 02 LS6 are 0.6-mm. longer than the valves in all other Gen III engines."
"With the higher lift (of the 2002 LS6 cam), we needed to reduce the mass of the valvetrain or start getting into a float condition," John Juriga commented. "We went to hollow stem intake and exhaust valves, very similar to what we used in the ’96 LT4. We pushed the edge with a state-of-the-art, 0.8-mm. (valve stem) wall thickness–very thin stuff. The exhaust stems are sodium-potassium filled."
Not only are ’02 LS6 valves taller, but these cutaways, made before the valve goes through the final machining steps, tell a bigger story: the significant mass reduction in hollow stem valves. The one at center right is the exhaust valve and its cavity is filled with the Sodium-Potassium compound.
The ’01 intake weighed 99 grams but the ’02 weighs only 76. The ’01 exhaust weighed 86 grams but the ’02 exhaust weighs 63 grams. The exhaust stems are filled with a 78% potassium/22% sodium mix to help cool the valve. "NaK" is unstable and may spontaneously combust when exposed to air with 50% or higher humidity. Do not cut open or shorten 02 Z06 exhaust valve stems.
Jim Hicks stated, "without the lightweight, hollow-stem valves, you loose about 300-400 rpm in limiting speed. You’re gonna be running into some significant valve train distress at 6200-6300 rpm.
Last edited by user 70810891082; Aug 26, 2008 at 11:10 PM.
