wats the difference between a UDP and a Harmonic Balancer? and doesnt the Neon come with a UDP?

 

its basically the same thing...just a different name
the only thing that i have ever noticed is that more people refer to a performance crank pulley as an underdrive.....i just call it a crank pulley...its easier

 

The UPD is lighter and frees up HP for the engine. It also has a smaller diameter than stock and tuns the accesories slower, so as not to rob power from the engine. And NO, a UDP does not come stock on the neon.

 

all motors produce vibrations or harmonics. a harmonic balancer's job is to lessen the stress on the crankshaft (think of it as a damper).

 

An underdrive pulley is never a stock piece, it is always aftermarket. The name means, as it implies, that accessory components attached to it are underdriven because the diameter of the UDP is smaller than the stock piece. It takes power to turn accessories like power steering and air conditioning, power that was meant to go to the wheels. UDP's don't add power, they reduce the amount of power going to the accessories by making them turn more slowly. Underdriving only does so much though, and the overwhelming majority of an UDP's power savings comes from bing lighter, which means the engine doesn't have to spend as much power turning the UDP as it sould a stock pulley.

The terms "harmonic balancer" and "harmonic damper" are generally accepted to mean the same thing, although many people do consider them different in one respect... A harmonic damper, which the Neon has stock, does absorb some of the noise, vibration and harshness (NVH) from the engine and attached components. It is press fit to the shaft and not a blanced component. A harmonic balancer does the same thing, but is keyed to the shaft and must be on the shaft if/when the engine is balanced.

Best of luck!