 Why do you set Chromoly Rods to 0 clearance?, Just wondering the mechanics behind it |
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| keske968 |
 Oct 29 2011, 09:25 AM
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Member  Group: Members Posts: 132 Joined: 5-September 06 From: Papillion, Ne Member No.: 6,778 Region Association: None  |
So I am rebuilding my engine and bought Chromoly pushrods from Raby. I have read that you set the valve clearance to 0.000 instead of the .006 that you would with an alumium rod. I am just wondering what are the physics behind that difference? It just seems that as things expand I would end up cooking valves. Hoping someone much smarter than me (not hard to do) can explain the reasoning behind this.
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| Jake Raby |
Oct 29 2011, 08:24 PM
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
To get those pushrods to expand .001" requires a temperature that will turn your heads into a pile of molten aluminum. The stock pushrods expand 4x more than ours.
All the testing we have done to come up with proper clearances has always supported the fact that zero lash was required. |
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Posts in this topic
keske968 Why do you set Chromoly Rods to 0 clearance? Oct 29 2011, 09:25 AM
Dave_Darling Aluminum expands a whole lot when heated. Chrome-... Oct 29 2011, 09:43 AM URY914 ^^^ Correct. Rate of expansion is much different. Oct 29 2011, 10:01 AM keske968 Thank you. Oct 29 2011, 03:50 PM
ArtechnikA The wood pushrods in my 356 engine don't expan... Oct 30 2011, 05:12 AM |
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