 OE Exhaust Valves, Sodium |
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| 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 
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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) |
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| r_towle |
Apr 2 2006, 09:10 AM
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#22
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Custom Member Group: Members Posts: 24,585 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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Here is my logic.
The car/engine was designed for longevity, not super performance... It was designed by alot of engineers...real automotive engineer, with dynos, testing equipment etc... the original valves last 30 years, provide 100k+ of service. They work with the stock motor design. If I am rebuilding a head, stock motor, stock vavle sizes...I use stock valves, sodium filled. I would never re-use valves, not worth it. The top of the valve stem is usually mushroomed, and needs to be re-ground, and re-hardened. not an easy DIY process. The new valves are 55 bucks ... I would say, dont re-use, but go with what the orinigal engineers specified for this motor...the same conditions...you will get another 100k plus from the motor. The original seat material has been upgraded, that was a failure point..so get the seats replaced. The valve guides are normally beyond service at 100k miles, so you will need to replace those as well. Rich |
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Posts in this topic
rdauenhauer OE Exhaust Valves Apr 1 2006, 10:04 PM
r_towle Im gonna ask a rhetorical question...
Did the ori... Apr 1 2006, 10:10 PM rdauenhauer Actually yes! and that IS the hope. <... Apr 1 2006, 11:56 PM Brando <... Apr 2 2006, 12:16 AM messix the valve stems are filled with sodium to isolate ... Apr 2 2006, 12:20 AM DNHunt 
