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can anyone tell me the compression (psi not ratio) for a EJ18E

thanx!

How about a general rule of thumb (assuming you do know the compression ratio)? Things such as valve timing, cranking speed, warmth of the engine, altitude, etc., affect the pressure, but the following will give a 'ball park' figure for a 'typical' engine in good condition.

 

Multiply the compression ratio by 18. For the 1.8L, with 9.5:1 compression, that results in 171 PSI.

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170 or better, but its not just that. An engine with a lot of miles having 150psi in all four cylinders is better then one with 170 160 150 175.

Yes, and it's also important that it takes about the same number of engine revolutions to reach relatively equal readings. For example, even if all four cylinders eventually peak at 175 PSI, with three of them requiring four compression strokes to achieve that but the remaining one needing seven, that indicates a problem.

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