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  #21  
Old 04-07-2024, 08:59 AM
mgarblik mgarblik is offline
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The overall cranking compression numbers are low across the board. That does NOT mean something is wrong with the engine. 1. Was the battery fully charged and cranking fast through the entire test? 2. Was the carburetor held at WOT during the test? 3. Were all the plugs removed during the test? 4. Do you happen to recall what the first puff reading was on each cylinder? First full puff reading should be at least 50% of the final reading of 5 full puffs. IMO, the difference between wet and dry readings does not indicate a piston ring issue. If the engine has been running rich for years like your plugs indicate, a running decarbonization process could restore the valve to seat seal which may be the cause of the low compression readings. This can be accomplished with a variety of chemicals and top engine cleaners run through a vacuum port into the intake of a fully warmed up engine at 2500-3000 rpm's Some people just use water for this. I like a 50-50 mix of top engine cleaner and water. It will make a HUGE, HUGE amount of smoke when you do this process so be prepared.

  #22  
Old 04-07-2024, 12:38 PM
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OCMDGTO OCMDGTO is offline
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Not to go against Team Qjet but plenty of us run Holley Double Pumpers on the street. I've been running them 40+ thousand miles and always without a choke year round. Your oil consumption isn't bad enough for a rebuild. I'd check timing first and get a rebuild kit for that carb. It is filthy looking in the primaries. Not sure what your fuel quality is like there, but I've had greater success with non ethanol. I periodically take off the fuel bowls and blow out the air bleeds.

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69 GTO Liberty Blue/dark blue 467, 850 Holley, T2, Edelbrock Dport 310cfm w Ram Air manifolds, HFT 245/251D .561/.594L, T400, 9" w 3.50s 3905lbs 11.59@ 114, 1.57/ 60'
  #23  
Old 04-07-2024, 07:14 PM
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Heybuck Heybuck is offline
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Just to throw my hat into the ring here, I can't see anywhere that you have done a leak down test which might possibly explain the varying compression values.

I would certainly be doing one before any thoughts on major engine out works take place.

JMHO Ian

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