[freeride59]

I have to put in my 2 cents here, I am a test engineer in the aerospace industry and I perform vibration tests on complicated mechanisms regularly , I am also a car guy.

Yes, you can put one these underdrive pulleys from NST or UR gain a couple HP and most likely never have a problem. If you did have a crank failure you couldn't prove it was the pulleys fault anyway. The guys who sell these parts know this, so they have to BS you and tell you why the damper is unnecessary.

The fact is there are hundreds of engineers that work for Honda studying engine dynamics, performing FEA analysis on crankshafts and running engine durability tests. If they discovered that the damper was unnecessary they would remove it in a heartbeat.

The function of a harmonic damper is just that, to dampen the harmonic vibrations in the crankshaft caused by the explosions in the combustion chamber. The explosion on top of the piston is like a hammer whacking the the connecting rod , exciting the natural frequency of the crank. Using a mass damper system the harmonics are absorbed and converted into heat energy.


* By the way these vibrations have nothing to do with the rotating components being out of balance.

* the timing belt or the accessory belt cannot absorb and/or dampen the harmonics, it must be a mass damper system .

* the harmonic damper is not used to keep noise down in the engine compartment, the natural frequency of the crank is most likely audible to dogs and birds not humans.

The removal of the damper will result in a slow degredation of the crank. Most likely the car will be junked or wrecked before the crank fails.

The thing that pisses me off is the arrogant attitude that UR & NST have, they want you to believe that they are more knowledgable of engine dynamics than the hundreds of engineers at honda. The K20 engine is an engineering marvel, don't disrespect the engineers at honda, they make a killer engine.