Was the exhaust valves the only one to be the sodium filled? Did i pay too much? Thanks
sodium valves, how do i know?
Thread Starter
Burning Brakes
Joined: Oct 2004
Posts: 984
Likes: 23
From: Florence SC
sodium valves, how do i know?
I just bought a set of 243 heads, was told they were from a 02, z06. the springs have a blue stripe on them, how can I confirm they have the sodium filled valves? I ended up getting them for $600, did I shoot myself in the foot on these? 
Thread Starter
Burning Brakes
Joined: Oct 2004
Posts: 984
Likes: 23
From: Florence SC
Drifting
Joined: Jan 2012
Posts: 1,341
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From: Hopatcong New Jersey
$600 is on the high end...I see them go for 400-475 all the time in the c6 for sale section...I don't think the sodium valves are worth an extra $150-200 to be honest.
Tech Contributor
Joined: Jan 2007
Posts: 19,398
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From: Dyer, IN
If they came with upgraded aftermarket springs, I'd say you did well. If they have stock springs, which are particulary known to break on 02's.....I'd say that's a little steep for my blood.
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Pro
Joined: Aug 2010
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From: Montgomery Texas
The sodium helps to keep the head of the exhaust valve cool, by conducting heat away from the head and down the stem. This is not necessary for the intakes, since a) they are not subjected to the same temperature extremes and b) the incoming charge provides a cooling effect.
Team Owner
Joined: Sep 2003
Posts: 43,084
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From: Raleigh / Rolesville NC
The sodium helps to keep the head of the exhaust valve cool, by conducting heat away from the head and down the stem. This is not necessary for the intakes, since a) they are not subjected to the same temperature extremes and b) the incoming charge provides a cooling effect.
also the light wt valves are good for up to 7200 rpms with out valve float
the stock valves or even Stainless Steel valves have a max ~6500 rpms, but still may experience valve float above 6500 rpms
These rpm ranges is were a cam with a max of .575 really produces.
Melting Slicks
Joined: Jun 2012
Posts: 3,163
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From: Oceanside California
Dont feel bad about what you paid. Its normal for real LS6 243 heads to go for that much. But if they are normal 243 head, the seller took you. If you weigh the exhaust valves at 63-65 grams they are sodium filled. around 88 grams and they are not.
(Not to argue with Lucky at all, but 63 and 88 grams are the specs I have wrote down). These are just weights that you might see.
(Not to argue with Lucky at all, but 63 and 88 grams are the specs I have wrote down). These are just weights that you might see.
Thread Starter
Burning Brakes
Joined: Oct 2004
Posts: 984
Likes: 23
From: Florence SC
Dont feel bad about what you paid. Its normal for real LS6 243 heads to go for that much. But if they are normal 243 head, the seller took you. If you weigh the exhaust valves at 63-65 grams they are sodium filled. around 88 grams and they are not.
(Not to argue with Lucky at all, but 63 and 88 grams are the specs I have wrote down). These are just weights that you might see.
(Not to argue with Lucky at all, but 63 and 88 grams are the specs I have wrote down). These are just weights that you might see.
Tech Contributor
Joined: Jan 2007
Posts: 19,398
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From: Dyer, IN
I would not think of arguing with you, based on your extensive automotive experience.
Melting Slicks
Joined: Jun 2012
Posts: 3,163
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From: Oceanside California
I was just giving another possible weight he might see, yours may be what he comes up with. Then I will alter my specs.
OP: Ill be interested to see what you come up with.
Burning Brakes
Joined: Oct 2004
Posts: 931
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From: Rowlett, Texas
The 243 valve stems are 0.024" longer than other LS valves, and it's all above the spring keeper. So, theoretically, You might be able to compare the 243 with a std head without removing a valve. You could eyeball or measure the distance from the top of the valve spring keeper to the top of the valve stem and compare, looking for the .024 longer stem on the 243. But removing and weighing a valve seems pretty easy and more difinitive.
DG
DG
Le Mans Master
Joined: Mar 2002
Posts: 5,955
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From: PNW
See page 5 of the linked PDF .. it says:
"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."
http://www.cadillacfaq.com/faq/answe...-article-2.pdf
The other LS6 (Part 1) write up by Hib Halverson:
http://www.cadillacfaq.com/faq/answe...s6-article.pdf
"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."
http://www.cadillacfaq.com/faq/answe...-article-2.pdf
The other LS6 (Part 1) write up by Hib Halverson:
http://www.cadillacfaq.com/faq/answe...s6-article.pdf
Race Director
Joined: May 2004
Posts: 15,866
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From: PA
I would recommend replacing the springs with a new set of LS2 blue springs before you install them. Not sure what springs you have on there with a blue stripe. New LS2 springs are only $75 from GM, worth the peace of mind IMO, springs failing seem to be the most common cause of engine failure on the LS6.
Thread Starter
Burning Brakes
Joined: Oct 2004
Posts: 984
Likes: 23
From: Florence SC
Bad news for me
You already know the answer, 88 grams on the exhaust valves. Damit, and to top it all off the more I look at them I doubt they came off of the same motor. one head is a lot cleaner than the other and the valve looks fresher also. 
Melting Slicks
Joined: Jun 2012
Posts: 3,163
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From: Oceanside California
