Aftermarket Crank Pulley

[TurboWarrior]

I just have a question. Its bugging me don't know why.

The stock Crank Pully is a Harmonic Balancer. Which means its more than just a pulley right? As in its acting as a balancer for the crankshaft?

If thats true whats the deal with these?

^Is this an accident waiting to happen or are they safe?

 

[mkIIIman089]

The deal is... there is a lot of controversy over those, because they are not dampers like stock one is.

I would never use one, its an "accident" waiting to happen.

The stock isn't balancing anything, its just lessening vibrations.

 

[TurboWarrior]

I see. If the stocker lessens vibrations that means that those vibrations potentially increase engine wear at least right?

 

[silvergsx623]

I see. If the stocker lessens vibrations that means that those vibrations potentially increase engine wear at least right?

Correct! save those bearings and use a pully that has a Harmonic Dampener!

 

[jdub]

The stock isn't balancing anything, its just lessening vibrations.

Kinda, sorta true...not completely accurate. The stock damper is balanced, you can see the drill marks where that was done to prevent the damper from contributing an oscillation vibration to the harmonics produced by the crank. It's purpose is to dampen (reduce the amplitude) of harmonic vibration...a well balanced crank with matched weight rods/pistons will help even more.

 

[TurboWarrior]

Thanks I needed to know for sure! $99 i thought it was too good to be true.

 

[supraman7mgte]

$99 bucks MINUS the cost of having your bearings replaced? what a deal!

 

[mkIIIman089]

Kinda, sorta true...not completely accurate. The stock dampner is balanced, you can see the drill marks where that was done to prevent the dampner from contributing an oscillation vibration to the harmonics produced by the crank. It's purpose is to dampen (reduce the amplitude) of harmonic vibration...a well balanced crank with matched weight rods/pistons will help even more.

Well, so it isn't balancing anything, and the pulley itself is balanced. If I'm understanding you correctly. If you want to bring it out on a technicality, I should have said it doesn't act as a counterbalance to the engines internal rotating assembly? You seem to be trying very hard to be like jetjock.

On the well balanced comment, I thought when we talking about harmonics we were talking about much higher frequency vibrations then a non-perfectly balanced rotating assembly would be producing... (Please, correct me if I'm wrong)

 

[jdub]

This motor is full of "technicalities"...something a lot of folks seem to ignore. Tell you what, if you're interested in what harmonic vibration is and what it does I suggest you read up on it. It's actually torsionial harmonic vibration...the frequency depends on the natural resonance of the crank and the rpm it is turning at. But I digress...I wouldn't want to risk insulting your intelligence.

But I can promise you this, the crank damper had better be balanced to do it's job.

 

[IJ.]

Our motors use 0 balance pullies and flywheels meaning they don't contribute to the overall balance of the motor and in themselves are balanced.

The front pully acts as a shock absorber to catch the twist of the cranshaft during firing pulses, the more hp the bigger the bang the greater the deflection therefore the bigger the damper and thicker the elastic ring needs to be.