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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 4 times for a complete cycle. That means it takes 1440 degrees to make a full cycle. Therefore it is difficult to denote exactly where the crank degree is. Therefore crank degree is usually denoted at Before Top Dead Center or After Bottom Dead Center.

A good example is spark advance. Spark Advance is usually 40 degrees before top dead center.

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