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Camshaft Duration

What is Duration?

Camshaft Duration
Camshaft Duration
When we are talking about Duration we are talking about the degrees that the cam lobe creates lift. Typically this number is around 270 degrees (but this is out of 720 degrees not 360).

What you need to know

First of all you need to realize the Camshaft rotates at half the speed of the crankshaft. That means when we are talking about duration of a camshaft we are talking about 720 degrees not 360 degrees for the crankshaft.

Next the Tappet. The Tappet is the pushrod or camshaft side of the Lifter. The new way of measuring Duration is .050 of lift on the Tappet.

Programs that take Camshaft Duration into account

We have 3 programs that work with Camshaft Duration when conducting Engine Simulation.Engine Analyzer v3.4, Engine Analyzer Plus v3.4. And Engine Analyzer Pro v3.9 also uses Camshaft Duration in Engine Simulation.

And we have 5 other programs that take Camshaft Duration into account when making calculations. Compression Ratio Calculator v2.3, Compression Ratio Calculator Plus v2.3 Port Flow Analyzer v3.5 with Valve Opener and Engine Log Book v1.1.