Underdrive Crank Pulley

An underdrive crank pulley is considered to be an accessory for your car, where the stock crank pulley is replaced with a high-performance component. For those seeking to receive more power and greater performance from your car, an Underdrive pulley will definitely have a significant effect.

Underdrive pulleys being used from the 1950s where they would only be seen used in race cars. The main use of these pulleys back then was to lower the load placed on the other components. Race cars were pushed to the brink and many of the machineries got damaged until they were introduced. They did not fall under the spotlight until mid-to-late 1980s, when they received a significant amount of enthusiasm and interest from all the main car fanatics. This was all possible because of the introduction of the single serpentine belt.

The usual scenarios for underdrive crank pulleys are that they are sold as performance boosters, components that will enhance the overall output. This particular performance booster works by intensifying the horsepower and torque produced by your engine which it manages to achieve by lessening the parasitic drag that is encountered by components that work using belts; although the most vital accomplishment of the pulley is decreasing the moment of inertia experienced. Although the total horsepower gained from using only underdrive pulleys is not that noticeable, usually 1-4 horsepower, the output may vary depending on the size and strength of the engine.

Unlike many beliefs, the underdrive crank pulley does not produce more horsepower from nothing. It merely decreases the amount of power that is wasted on the overdriven components, thus freeing up that power so that it is delivered to the wheels. With the larger pulley attached, the workings and gears will be driven slowly which will significantly lessen the horsepower lost due to parasitic drag. Simply put, less waste equals to more output.

Aside from slightly increasing the performance of your vehicle, the underdrive crank pulley has many other benefits. As the main task of the pulley is to reduce the amount of load and stress placed on all the other components and machineries, this device can actually increase the overall lifespan of each individual apparatus. Examples are basically the parts that require the horsepower from your engine; such as the power steering, air compressor, alternator, etc.

As many people might think that such a beneficial piece of equipment must have a few drawbacks or effects. But in the case of an underdrive crank pulley, there practically is none. There are no examples of this pulley conflicting with any other device in your engine or cause any adverse effects. The general view of most underdrive pulley owners is that this modification is a simple replacement of the original component, which just provides more power to your car.

But keep in mind a few pointers if you are thinking of installing an underdrive crank pulley on a street car. Make sure that there isn’t more than 15-20% underdrive, because too much can have serious side effects on your car. The equipment that requires horsepower may not receive that much because of too much underdrive. Components such as the alternator, air conditioning systems or even your power steering will not be as effective, leading to sudden drops in alternator voltage, power assist and air conditioning. Such effects will be distinctively noticeable when the car is idle. If such were the case for a race car, it would not have caused much alarm but for a car that is driven regularly on streets, it may turn out to be a serious irritation.

In conclusion, an underdrive crank pulley is a wonderful customization that you can have for your car. The increase in horsepower and longevity of the lifespan will be something that you will come to adore; and such improvements are few of the best you can have when compared to the value of money that you receive.

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