How many of us are there? Owners of Dodge based RV's?

The compression ratio on the 360 for that year was (allegedly) 8.5:1. And since I am at altitude, the standard 14.7 PSI won't apply. Since that pressure is about 85% (equating to about 12.5psi) which means that the pressure should be at or around 105 PSI under IDEAL conditions.

I'll get a pressure gauge tonight- providing the weather in Denver doesn't go absolutely nuts as it tends to in late summer.