Characteristics of an impulse swirl meter (ISM), which is a feasible way to measure the angular momentum flux of swirl directly in a steady-flow rig test, are investigated by changing the size of honeycomb flow rectifier, the type of intake port and rectifier position. The angular momentum determined by the ISM has a tendency to decrease with the increase in the drag force of the rectifier, but soon approaches a stable value. The angular momentum without the ISM is larger than that with the ISM. The angular momentum by the ISM has its maximum at the position nearest the cylinder head from which it decreases more rapidly than that by a vane-type anemometer. The ratio of swirl intensity determined by the ISM to the vane anemometer is influenced by intake port, intake valve lift and distance from the cylinder head.