Crank Degree

Crank Degree is use to denote where critical events occur in the 4 stroke cycle engine. Such as spark, Piston Position, valve lift etc. And it is directly correlated with the cam degree. The camshaft rotates at half the speed or revolutions as the crankshaft. So for every 360 degrees of rotation for the crankshaft the camshaft(s) only rotate 180 degrees.

4 stroke engines rotate 2 times for a complete cycle. That means it takes 720 crank degrees to make a full cycle. Rather than saying an event occurs at 25 or 385 degrees, events in crank degrees are often referenced to where they occur relative to TDC or BDC, like an intake opening event on the cam could be 65 degrees BTDC (Before Top Dead Center).

Another good example is spark advance. Spark Advance is usually 30 to 40 degrees before top dead center.

All of our Engine Analyzer (Engine Simulation) programs allow you to work with Crank Degrees. This includes Engine Analyzer, Engine Analyzer Plus and Engine Analyzer Pro.