Dwell angle is a crucial parameter in ignition systems, particularly in older vehicles with mechanical distributors. It refers to the duration, measured in degrees of crankshaft rotation, that the ignition points are closed, allowing current to flow through the ignition coil. Accurately setting the dwell angle ensures optimal ignition timing, leading to improved engine performance, fuel efficiency, and reduced emissions.
Checking and adjusting dwell angle is a relatively simple procedure that can be performed using a dwell meter, a specialized tool designed to measure the duration of electrical pulses. By connecting the dwell meter to the ignition points, technicians can determine the dwell angle and compare it to the manufacturer’s specifications. If necessary, adjustments can be made by rotating the distributor housing until the desired dwell angle is achieved.