How much horsepower do underdrive pulleys add?
8 to 15 hp
Underdrive pulleys will yield a small increase in horsepower anywhere from 8 to 15 hp. This is accomplished by reducing the amount of power needed to drive the engine accessories that eat up precious horsepower.
What does a 25 underdrive pulley do?
So what do underdrive pulleys do? Underdrive pulley systems increase engine horsepower by reducing the amount of power required to drive external engine accessories. For example, the alternator, power steering, water pump and air compressor rob horsepower from your engine.
Are underdrive pulleys worth the money?
Underdrive pulleys, when applied to the accessory components of a vehicle, drive the components at a lesser speed because of their increased diameter size. As far as an upgrade, they provide one of the cheapest returns for the money spent when it comes to actual performance and horsepower gains.
Do underdrive pulleys increase torque?
The GFB lightweight under-drive pulleys do not increase the amount of torque or power developed by the engine. They simply reduce the amount of mass that the engine must accelerate.
What does an under drive do?
Underdrive pulleys increase engine output by reducing the draw of the engine’s accessories by slowing them down and reducing the horsepower (HP) they use. Additional and significant performance improvements can be seen by reducing the weight of the pulley versus the original pulley.
Do underdrive pulleys actually work?
Horsepower gains from underdrive pulleys can vary by vehicle, engine, number of accessories and the amount of underdrive (improvements of up to 5–15 HP at the wheels have been seen). Additional and significant performance improvements can be seen by reducing the weight of the pulley versus the original pulley.
Are underdrive pulleys bad?
Poorly engineered underdrive pulleys can cause unwanted side effects; this is due to not spinning the alternator, power steering, and/or air conditioning fast enough. This leads to low alternator voltage, weak or no power steering assist, and weak or no air conditioning effectiveness, especially at idle or low RPM.
What’s the difference between overdrive and underdrive?
The technical definition of overdrive is this: If the driven gear is smaller—and therefore spins faster than the driving gear—that is overdrive. If the driven gear is larger—and therefore rotates slower than the driving gear—that is underdrive.
How much horsepower can you get out of a 1994 Mustang GT?
A Hard-Charging Year With The Pony Express
| GENERAL/POWERTRAIN | |
|---|---|
| Body style | 2-door, 4-passenger |
| Engine displacement, ci/cc | 302/4942 |
| Horsepower, hp @ rpm, SAE net | 215 @ 4200 |
| Torque, lb-ft @ rpm, SAE net | 285 @ 3500 |