OE Exhaust Valves, Sodium |
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OE Exhaust Valves, Sodium |
914werke |
Apr 1 2006, 10:04 PM
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#61
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"I got blisters on me fingers" Group: Members Posts: 10,116 Joined: 22-March 03 From: USofA Member No.: 453 Region Association: Pacific Northwest |
I know Jake suggests tossing these, but unfortunantly Im rebuilding a set of heads. Id like to keep them stock, but Im more concerned about longevity.
Is there anything that can be done to improve thier function? Cryo? (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif) |
J P Stein |
Apr 3 2006, 12:43 PM
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#62
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Irrelevant old fart Group: Members Posts: 8,797 Joined: 30-December 02 From: Vancouver, WA Member No.: 45 Region Association: None |
The sodium transfers heat from the head to the stem of the valve.
The stem transfers the heat to the valve guide & oil......when the guide is excessively worn, this heat transfer starts to break down. Left to it's own devices this does not get better, but worst.....over heating the valve which can burn or just snap off. |