Less than 115 psi: poor low speed response, hard starting. Pistons and cams not well matched or worn rings, valves.
125 to 145 psi: OK for stock or modified street motors. On the low end for a stock street motor.
145 to 165 psi: OK for modified street motors. Static pressures in this range will be very good for street motors.
165 to 185 psi: Marginal for large displacement street motors, possible hard starting, detonation and overheating.
Over 185 psi: High performance numbers. Motors over 185 PSI may need compression releases and/or octane booster.
The above recommendations are not absolute but the point is that static compression is important. Proper matching of cams and compression ratios will allow engines to be modified for more performance and still run smoothly in street applications.
ratio are related but the definition of each is different.
duration in a camshaft is not necessarily a good thing.
1. Compression ratio set too high.
2. Intake cam duration too short.
3. Intake cam closing point advanced too much.
or "pinging" and possible rapid starter motor wear.
RPM torque and throttle response.
pressure in your engine is not difficult.