AVBM & Adjustable Voltage Information

Some Mechman alternators are available with the optional adjustable voltage feature. The "AVBM" module allows the user to increase the charging voltage of their Mechman alternator to optimize their 12v system, or to raise the charging voltage to suitable levels for 14 volt or 16 volt batteries. Safe voltage levels must be maintained for your batteries and for your vehicles electronics, so consult with a Mechman sales representative before ordering.

PCM Regulated Vehicles

Many late-model vehicles have their alternator charging voltage regulated by the vehicle's engine computer. A high output alternator will produce more amperage, but will not change the charging voltage on a PCM controlled vehicle. Even though the voltage will remain the same, rest assured that you will be getting more amperage supplied to keep your battery charged.

Alternator & Connector Identification
Alternator & Connector Identification

Alternator Output Ratings

Mechman alternators are rated at 2400rpm and 5400rpm of ROTOR speed. This equates to 800rpm and 1800rpm of engine speed with the typical 3:1 pulley ratio. Depending on the size of the vehicle's crankshaft pulley diameter, some vehicles may have less or more than a 3:1 pulley ratio, which will result in more or less rotor RPM at any given engine rpm. If you need assistance in calculating exact idle output, or output at a specific engine speed please contact the Mechman technical assistance department. Be sure the have the diameter measurement of your vehicle's crankshaft pulley and exact engine idle speed available when calling.

Belt Information

  • Belt Condition- For best performance it is recommended that you use a new premium belt when installing a high output alternator.
  • Belt Tension- High output alternators require more effort to turn when under load. This requires not only that the belt be in good condition, but that it is properly tensioned. Poor belt tension can lead to belt slip and reduced performance.
  • Belt Length- Some Mechman alternators will require a shorter or longer belt in order to provide proper belt tension.
  • Belt Slip- Improper belt tension, poor belt condition, improper belt length can cause belt slip to occur. Belt slip may also be experienced under extreme conditions due to the increased belt load, particularly on vehicles with single v-belt or smaller serpentine belt systems.
  • Underdrive Crank Pulleys- Underdrive crankshaft pulleys are not recommended for use with certain high output alternators. Smaller diameter underdrive crankshaft pulleys reduce alternator rotor speed, and may cause poor low-speed output on some models. For racing applications where a less than 3:1 pulley ratio is required to prevent from over speeding the alternator, consult with a MechMan sales associate for the best alternator for your application.