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Old 09-02-2010, 08:34 PM
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ericnova72 ericnova72 is offline
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I think the only running 3-4 initial advance is part if not most of the problem. you need to get that up into the 14-18 range. I am not familiar with your Mallory distributor so you may need to work with it(weights, springs, total stops) to ensure this doesn't put your total timing over 38.

You are setting it with the vacuum advance hose disconnected, right??

Lifter pump-up only happens in an over-rev situation, not in normal operation, you are looking in the wrong area unless something is wrong with the lifters from the get-go like incorrect sizing of parts in them, incorrect assembly, etc. Oil pressure alone, no matter how high it is, can't cause lifter pump-up. High pressure/thick oil only slows the lifters return to normal lash after it has been pushed into an over-rev over-clearance situation. Valve spring pressure is way higher than oil pressure.
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