Hi Keith,

Easier method of checking pump pressure, as well as the actuating is to to use a T fitting with a gage. It's the practical way, theoretical values might be off as there is no constant temperature and I don't think the value will be linear, rather will be exponential as the pump works on a membrane , depending of the engine RPM and then letting the engine temp to stabilize before taking readings or doing calculations will be the way.

The gage is the best way for sure, probably is easier to get the gauge in inches of water and then do the conversion if you want to make a study.

Hope we are not boring anyone, sorry if we do.

Best regards