OE Exhaust Valves, Sodium |
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OE Exhaust Valves, Sodium |
914werke |
Apr 1 2006, 10:04 PM
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#21
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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) |
davep |
Apr 2 2006, 06:59 AM
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#22
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914 Historian Group: Benefactors Posts: 5,151 Joined: 13-October 03 From: Burford, ON, N0E 1A0 Member No.: 1,244 Region Association: Canada |
Absolute nonsense. The liquified sodium in the valve stem sloshes back and forth to transfer heat faster from the valve head to the stem. Then through the valve guide and into the head. This design is like a heat pipe that is so much in vogue in heat transfer circles today, but does not use two phase operation and instead requires mechanical motion. Now titanium is a good insulator, and tends to trap the heat in the valve head, comparatively speaking. So this lightness of the Ti valve is offset by its heat transfer characteristics. |
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