Pressure between 80 and 150 psi is considered good.Do an indicator test and if the it changes color than head gaskit is done for. http://www.arrowheadradiator.com/head_gasket_or_combustion_leak_test.htm
I can confirm that you don't always find water in the oil, having had this on a Honda CR-V recently. I was very surprised and therefore after lots of cooling system overheating potential fixes, I realised it was the head gasket. No sign of power loss either - very strange. Took a long time to diagnose for this reason, then stripped the engine, skimmed the head and rebuilt.
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Pressure between 80 and 150 psi is considered good.Do an indicator test and if the it changes color than head gaskit is done for.
http://www.arrowheadradiator.com/head_gasket_or_combustion_leak_test.htm
I can give you part of your answer: yes you can blow a head gasket and not get water in the oil. The pressure can leak in to the coolant system.
I'm not sure what the pressure should be on your car but the difference shouldn't be very much.
I can confirm that you don't always find water in the oil, having had this on a Honda CR-V recently.
I was very surprised and therefore after lots of cooling system overheating potential fixes, I realised it was the head gasket. No sign of power loss either - very strange.
Took a long time to diagnose for this reason, then stripped the engine, skimmed the head and rebuilt.