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: 10,138 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) |
Twystd1 |
Apr 3 2006, 06:03 PM
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#62
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You don't want to know... really..... Group: Members Posts: 2,514 Joined: 12-September 04 From: Newport Beach, California Member No.: 2,743 |
Many spec racing (NASCAR and others) V8 engines use spray bars for cooling the valve springs and splashing the rollor rockers.
The oil transfers the heat away from the springs so they last the race. With the advent of spray bars, better alloys like Ti, better heat treating, ceramic coatings and carbon coatings, and the always controversial Cryogenic metal treatment. Broken valve springs are rarely a problem in race engines. I did the spray bar setup on a type 4 a while back as it had Pauter roller rockers. A couple of dune buggy bretherin had told me this was the way they kept their valve train alive on long races.. (Baja500, etc.) I think it was Jake or Fat that showed pics of a Type4 spray bar setup on the web... Hey Aaron... you have the link???? I wish I had the coin/time for a full tilt 3 stage drysump and evac system. Then again.... I would have to build a 8K + RPM to need one. That will get ALL the oil exactly where I want it. And in the volumes and pressures the build dictates. Thats on my list of have to do before I die projects..... (works in a type1 and v8s) This is really a great thread... Great example as to why I come here... To learn... THANKS..!! Clayton |