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Old 03-15-2016, 11:32 AM   #1
volksworld
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Re: Low Vacuum? With good compression?

if i had it that far apart i'd just change cam and lifters too just so you know where you stand...small blocks have been known to flatten cam lobes...thats why i loved bug engines...not having to consider a bad chain or hydraulic lifters made them a heck of a lot easier to diagnose
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Old 03-15-2016, 03:38 PM   #2
cleszkie
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Re: Low Vacuum? With good compression?

If the timing chain has been replaced in the past (as it appears to be), that increases the odds that a cam swap also happened, which could mean a cam profile that generates less vacuum. Judging by how clean the post on the cam that engages the cam gear is, I'd say that the cam was replaced. Remove the cam gear and see if the cam grind number is identified on the end of the cam. This should give you an idea of what vacuum the cam should be making.

Last edited by cleszkie; 03-15-2016 at 03:44 PM.
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