Hello ,
if you compare some measurements, you have to know in which condition the measurements are done. I open always full the throttle on a warm engine.
The important result should be that all values are nearly on the same level.
If some value is very low , I fill oil in the spark plug hole and wait 2 minute and check again. If the value is higher, it can be a indication of bad piston rings or cylinder wearing.
My last measurements on my BT7 engine was 11 bar
So good luck .
Michael- who has to weld actually his rocker panel