cylinder compression on Chevy 229 c.i. V6 (3.8L)

Question:

I had all 6 plugs out, but the engine wasn’t hot.  It seems odd that they would suggest a minimum but not a maximum pressure. > Joe, > According to GM: >  The lowest reading cylinder should not be less than 70% of the >  highest, and no cylinder reading should be less than 689 kpa (100 psi).  

Perform the test with engine at normal operating temperature, – Hide quoted text — Show quoted text ->  spark plugs removed, and throttle wide open. > GMdude

Response:

Joe,     That is not so odd. It’s the minimum psi that is important for the engine to run. And the difference between the cylinders to run evenly. GMdude

Response:

Sounds like a lot of carbon buildup on the piston face. the ideal compression is pretty much anything over 100 psi

– Hide quoted text — Show quoted text -> I have a 1984 Chevrolet El Camino with a 229 V6.  I recently measured the > cylinder compression at 180 p.s.i. (+/- 5 p.s.i) on all 6 cylinders.  What > is the ideal compression for this engine?

Response:

Is this a bad thing?  If so, is it easily correctable? And 180 psi IS over 100 psi, is that "ideal"? – Hide quoted text — Show quoted text -> Sounds like a lot of carbon buildup on the piston face. the ideal > compression is pretty much anything over 100 psi

Response:

Joe, According to GM:     The lowest reading cylinder should not be less than 70% of the highest, and no cylinder reading should be less than 689 kpa (100 psi).     Perform the test with engine at normal operating temperature, spark plugs removed, and throttle wide open. GMdude

Response:

I have a 1984 Chevrolet El Camino with a 229 V6.  I recently measured the cylinder compression at 180 p.s.i. (+/- 5 p.s.i) on all 6 cylinders.  What is the ideal compression for this engine?

Response:

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