Original H-O's
Average Air Flow

This calculator estimates the Average Air Flow for the cylinder head flow data selected from the pull down choices or entered manually. The calculator does this by computing the "Area Under Curve" (AUC) for the head air flow and dividing it by the number of data points. Since the calculator uses the composite trapezoidal-rule numerical integration method, the result is a slightly low approximation of the average CFM value.

If your valve lift is less than the lift of the flow data, enter only the flow up to the valve lift, i.e., if the valve lift is .514", input head flows to .500" valve lift.