Do you need much torque to turn a cam?
It would be wise to remember that at low RPM, the forces are regenerative, and especially on multi cylinder engines, the cam really doesn’t need much torque to turn..
How many revolutions does a camshaft have to spin?
That means the crankshaft has to spin twice for the cam to turn one revolution. That orientation is designed into all four-stroke engines. You will see that this Summit Racing cam offers duration in two different tappet lift specs of 0.006-inch and also at 0.050-inch.
What are the specifications on a camshaft timing card?
One area of confusion is certainly a camshaft timing card. All aftermarket and production camshafts use a series of terms and specifications to identify their operating characteristics.
How are crankshaft degrees expressed in Camshaft specs?
This is defined as the number of degrees of crankshaft rotation that each valve that spends off the seat. All camshaft specs are expressed in degrees of crankshaft rotation. Crankshaft degrees are used because that’s the easiest way to measure these points on the actual engine.
How does the length of a camshaft affect torque?
This will have all of the cam specifications on it, including cam lift and duration. Lift is the distance the valve travels to its maximum open position and is a key factor in torque production. Duration is the amount of time, measured in degrees of crankshaft rotation, that a camshaft holds a valve open.
That means the crankshaft has to spin twice for the cam to turn one revolution. That orientation is designed into all four-stroke engines. You will see that this Summit Racing cam offers duration in two different tappet lift specs of 0.006-inch and also at 0.050-inch.
One area of confusion is certainly a camshaft timing card. All aftermarket and production camshafts use a series of terms and specifications to identify their operating characteristics.
What is advertised duration on Summit Racing Cam?
The 0.004- or 0.006-inch spec is now called advertised duration. In the Summit Racing cam example, this is the amount of crankshaft rotation that begins once the lifter is 0.006-inch off the base circle and continues until the lifter is 0.006-inch off the bases circle on the closing side.