Frequently Asked Questions (FAQs)
1. Do pulleys increase HP?
Underdrive pulleys can potentially increase horsepower by improving engine efficiency and reducing parasitic power loss. Depending on the vehicle, engine, number of accessories, and the amount of underdrive, horsepower gains of up to 5-15 HP at the wheels have been observed. Additionally, reducing the weight of the pulley can provide further performance improvements.
2. Do lightweight crank pulleys make a difference?
The benefit of lightweight crank pulleys is more noticeable in lower gears, where traction is often limited. In higher gears, the difference may be less perceptible. While lightweight pulleys can provide some performance advantages, the impact may vary depending on driving conditions and other factors.
3. What does a crank pulley upgrade do?
A crank pulley upgrade, such as APR's Supercharger Crank Pulley Upgrade, increases the diameter of the factory pulley. This results in the supercharger spinning at a higher rate of speed, leading to increased horsepower and torque across the entire RPM range.
4. Is a smaller crank pulley better?
A smaller crank pulley can reduce parasitic power loss by slowing down the accessories driven by the engine. This can result in improved engine efficiency and power delivery compared to stock-sized pulleys.
5. What is a disadvantage of using more pulleys?
Using more pulleys requires additional space and can increase the risk of slipping or breaking ropes, belts, or chains. Continuous use can weaken ropes, making them more prone to breakage.
6. Do bigger pulleys increase speed?
Bigger driven pulleys relative to the driver pulleys will result in slower rotation but increased torque. Smaller driven pulleys will lead to faster rotation but reduced torque.
7. Do smaller pulleys increase HP?
Similar to underdrive pulleys, smaller pulleys can potentially increase horsepower by reducing parasitic power loss and improving engine efficiency. This can result in improvements of up to 5-15 HP at the wheels, depending on the vehicle, engine, and other factors. Additionally, reducing the weight of the pulley can provide further performance benefits.