stillen lightweight crank pulley

black09Z

Anybody got one yet? Is it worth the money?

ChrisSlicks

RCZ and Semtex both bought them but they don't have them yet.

BlueR32

i almost hate to bring it up, but does the stock pulley have a harmonic damper?

conversely, does anyone make lightweight pulleys for the non-crank items (alternator, water pump, AC)?

black09Z

What's that mean?

JoeyD

Harmonic dampers absorb vibration through the crank and prolong the life of the bottom end by reducing wear on bearings and such. They are less important the shorter your crank is. In other words it's not as important on a V-6 as it would be on a I-6.

__________________
When was the last time you did 230MPH in something with 4 seats?

RCZ

Hehe, the myth resurfaces. Harmonic Dampers is a never ending argument, like break-in.

We'll see what happens when I get it installed...

Oh and mine comes in tomorrow, I'll get pics up when I have it.

BlueR32

myth, as in fictional? torsional vibrations that lead to engine failure are definitely not myth.

harmonic amplification of such vibrations would occur at very specific rpms/frequencies, so their relevance in a passenger car, whose rpms vary constantly, is probably very low, hence the assumption that they are not needed or can be eliminated.

it IS a never ending argument, especially when people say things like "it didn't happen to me, so it must not be true," which is just as misleading as "stay away from this- i had an engine failure, so this part must have done it."

anecdotal/individual experiences mean nothing except as part of controlled study. unfortunately, such study is essentially never done with aftermarket car parts. so, we are left with having to make such decisions on precious little worthwhile information.

i am just curious to know if the stock crank pulley has a harmonic damper. if it doesn't, there's not a reason in the world to avoid an underdrive pulley. if it does, people should make their decision mindful that someone thought it was a good idea.

black09Z

Thanks for the info. Can't wait to see the pics, don't forget to tell us how much of a difference if any you notice

JTso

Is the stock crank internally balanced? If so, there's no harmonic damper. If you see a rubber band like ring as part of the pulley, that's the elastomer for absorbing operation noises such belt rotation sound. A harmonic dampering pulley is easy to spot such as those on domestic engines. Someone should take a picture of the pulley.

RCZ

No, not as in fictional, but I'm glad it gave you a chance to explain that for the folks who didn't know what it was for....

What I was getting at is exactly what you said later on. That everyone always talks about it and the effects of not having one, yet it becomes an argument about whether or not the car needs it. Just like whether or not the car needs a babying period during break in.

I am glad you know your stuff, but that begs the question as to why you have an R32?

I am kidding.

I'll let you know if my motor vibrates itself into pieces in a couple months

Josh@STILLEN

The stock pulley is not a harmonic damper, and the engine is internally balanced. There is a rubber piece for NVH reduction. This information is correct.

black09Z

So back to the first question, how is it?

RCZ

Didn't get a chance to install it over the weekend. Sorry, should be in this weekend though.

black09Z

I'm getting impatient! Lol. Stop teasing me!

SOLISIMO

The G37 isnt seeing any gains from them