Performance Underdrive Pulley Kits From BBK
BBK Performance billet aluminum pulley kits offer an affordable and simple way to get additional rear wheel horsepower.
Simply they reduce the power the engine uses to turn the front engine accessories - therefore that additional power goes to the rear wheels.
An underdrive pulley refers to either crankshaft or accessory pulley like an alternator or water pump pulley specifically designed to turn at a slower speed than stock.
When the the front engine pulley ratios are changed they will be rotated by the serpentine belt at a slower rate regardless of the vehicle. This means that they are under driven hence the term under drive pulleys.
This Underdrive is achieved by designing the main crank pulley to be smaller than factory and then usually the water pump pulley larger than the original diameter aswell as the alternator depending on application.
The end result is that the front engine accessory pulleys are slowed down from the original speed of the factory pulley system adding good performance improvements.
We have seen Improvements of up to 5-15 HP at the wheels depending on the vehicle.
BBK performance pulley kits are also manufactured from light weight billet aluminum that is CNC machined in house - this ultimately saves weight over the heavy stell OEM units and adds to additional power improvements becasue they are much lighter than the factory steel units.
BBK underdrive pulley kits offer great value and best of all in nearly all cases they can be installed using the existing factory belt - so there is no need to buy a new one.
Installing an under drive pulley kit is probably one of the best values in the aftermarket and we encourage new owners to make this one of their first modifications as they are a great "Bang for the buck"