How to Choose a Racing Alternator

Several factors have to be taken into consideration when choosing an alternator that is right for a racing application. For instance, the drag racer only has a short time on the track, so the charging is before and after the race. The circle track racer has a longer track time with constant loads, so charging time is during the race. Additionally, limitations on the location of an alternator, drive systems, and pulley ratios vary greatly for different types of racing.

The decision can be simplified by the following three step process:

STEP 1:

DETERMINE THE AMP LOAD

Calculate the total amount of amp load from the chart below. This will determine the output of the alternator needed for the application.

STEP 2:

INSTALLATION LOCATION

Determine where the alternator can be installed and how it will be driven.

STEP 3:

PULLEY SELECTION

The type of racing will determine the pulley ratio. For example, an overdrive pulley ratio is recommended for drag racing because it is best to charge while in staging and on the return slip. This enables the battery to be fully charged for optimum ignition when you pull to the line. In most cases, a pulley ratio of 1.75:1 or more is recommended for drag racers (see also “Power Pulleys”). For circle track racing, charging while on the track is necessary for long periods of time. For this reason a straight 1:1 pulley ratio is recommended. Powermaster has different styles of pulleys..