Excellent read here
http://robrobinette.com/S2000Compression.htm

If by Honda spec nominal comression is 1570 kPa or 228 PSI

then, with no leaks this is how much compression you can get filling the volume in with the air from cranking the engine. Remember, this is the max pressure reading over few cycles.
How then people are happily reporting 240-250 PSI readings? Any explanation aside of poorly calibrated gauge would be appreciated.

 

1)Engine RPM
2)Length of test session
3)Engine temperature
4)Carbon buildup in combustion chamber
5)Altitude

The idea isn't to hit 228psi on the head; the idea is that all cylinders are very close in numbers AND within specified range.
...

Lastly, and most common,

A poorly calibrated gauge.

At 240psi, it is a 5% difference. I'd say a +/-5% deviation in consumer grade, mostly chinese gauges is well within reason.

 

OK, thanks. Let's see.
RPM - should not vary too much as it is just starter cranking. Even if vary, should not make much difference on the pressure.
Length of test session - given enough cranks, should not matter.
Engine temperature - yes, big factor. But if done right at the warmed up engine should not be too much different (although 5% is not much). It's difficult to believe that all the people reporting 240+ PSIs were running real hot, as it takes time to prepare for the test and do it.
Carbon build-up- I have no idea honestly, but hope this should not affect the chamber volume too much.
Attitude - sure. How high we should go?

 

If everything I listed is not relevant, then the results are simply lying.

 

Ha-ha
It sure feels they do