What makes a cam "lope?"
Valve Overlap Requirement There has been little attention given to the correct answer.
There is some information given to state the results, not the cause.
The CAUSE is the pressure of air, at sea level 14.7 .lbs per square inch.
This "air pressure" is present in the engine exhaust system.
As we know, when the engine is throttled, the intake port pressure is MUCH lower than BARO.
Thus at IDLE exhaust gases can flow into the intake port when there is Valve Overlap.
The result of exhaust gases in a "fresh charge" can cause engine miss-fire.
Once this is understood, the cause, it is easy to create correct valve timing events.
Lance
There is some information given to state the results, not the cause.
The CAUSE is the pressure of air, at sea level 14.7 .lbs per square inch.
This "air pressure" is present in the engine exhaust system.
As we know, when the engine is throttled, the intake port pressure is MUCH lower than BARO.
Thus at IDLE exhaust gases can flow into the intake port when there is Valve Overlap.
The result of exhaust gases in a "fresh charge" can cause engine miss-fire.
Once this is understood, the cause, it is easy to create correct valve timing events.
Lance
