Cylinder Compression
Discussion
I got this from www.turbosport.co.uk.
"As said above there is no set pressure for an engine. Will depend on cranking speed, temperature of engine, cam overlap, how long you crank for, static compression ratio etc etc.
Just make sure you test all 4 pots exactly the same way. Most important IMO are hot engine (all plugs out), throttles held wide open and crank for the same number of engine revolutions each time. You should see the needle on the pressure gauge jump up quite a lot on each compression stroke and then it will add less and less PSI the more you crank. This is why it's important to standardise the test.
All cylinders should be within 10%, and hopefully in the 150 to 180 psi range."
Hope that helps.
"As said above there is no set pressure for an engine. Will depend on cranking speed, temperature of engine, cam overlap, how long you crank for, static compression ratio etc etc.
Just make sure you test all 4 pots exactly the same way. Most important IMO are hot engine (all plugs out), throttles held wide open and crank for the same number of engine revolutions each time. You should see the needle on the pressure gauge jump up quite a lot on each compression stroke and then it will add less and less PSI the more you crank. This is why it's important to standardise the test.
All cylinders should be within 10%, and hopefully in the 150 to 180 psi range."
Hope that helps.
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