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Old 12-28-2011, 08:03 PM
Dave Rifkin Dave Rifkin is offline
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Default Stupid question?

Can you tell the compression ratio of an engine via a compression test? My 350 / 350 Corvette is factory rated at 11.0:1 compression ratio but I have a feeling that someone rebuilt the motor with a lower compression ratio.

I don't want to tear into the motor if I don't have to.
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Old 12-28-2011, 08:52 PM
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PxTx PxTx is offline
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Default Re: Stupid question?

It isn't very scientific and overlooks some major variables like camshaft selection but it may help to put a compressioin gauge and let us know what you find.

i had a 13:1 that had about 180 psi using a compression gauge while cranking.
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Old 12-28-2011, 10:20 PM
COPO PETE COPO PETE is offline
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Default Re: Stupid question?

Not a stupid question, but no, you can't.(that way) The duration of your camshaft will give you different reading on your gauge.
If you know someone with the "wistler", it will tell you the compression reading. Not very many people have this. Race track tech in round-e-round or certain race organizations. The Pure Stock Drags guys use one.
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Old 12-29-2011, 02:52 AM
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Plowman Plowman is offline
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Default Re: Stupid question?

Pinging sensitiveness can be tested with cranking compression. *Paul
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Old 12-29-2011, 03:09 AM
Salvatore Salvatore is offline
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Default Re: Stupid question?

is there a problem with the performance or you just wondering Dave?
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Old 12-29-2011, 01:22 PM
Dave Rifkin Dave Rifkin is offline
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Default Re: Stupid question?

Sam,

Not a problem with how the car runs, although I do think it should be a lot faster for an L46 car. I was thinking about pulling the motor so I could detail the engine compartment and the engine.
If the compression isn't correct I would want to rebuild the motor so it is performing as it should. Of course I don't really have the funds to rebuild the motor at this time. I was thinking about identifying the parts I would need and start purchasing them as I get the money. Then, once I have everything gathered I could pull the motor and detail everything.
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