Cross

iTrader: (10)

If I worded that correctly most know what I am asking... however I probably did not.

What I want to know is this;
Is our motors crank internally balanced or externally? I have a UDP on mine and it does not have the Harmonic Balancer/Crank Pulley that was stock on it... I have a spare one but the rubber is shot as most are.

I have been looking at aftermarket ones but wanted to know for sure before I drop close to 200 for one.

James Montigny

iTrader: (13)

The stock crank is balanced externally at the rear using a weighted flexplate (or flywheel)
The hub and pulley (front) are neutral.

Your UDP should also be neutral.

Cross

iTrader: (10)

So its really just an added bonus. Alright then I am no longer as worried as I was reading a few other posts.

1994Z28Lt1

iTrader: (1)

balanced or unbalanced you still need that harmonic balancer on that engine

here is one of the better write-ups for why a harmonic balancer is needed

Otherwise known as vibration damper, harmonic balancer is a device attached to the vehicle’s crankshaft to minimize torsional vibration. As the cylinders fire, the crankshaft transports the power. The front section of the crankshaft suffers from the impact of the said power, due to this, it often moves before the rear part of the crankshaft. And this movement yields a twisting motion. Once the power leaves the front, the halfway twisted shaft unwinds and then snaps back in opposite direction. Even though it is small, the unwinding process gives torsional vibration.

To minimize this vibration, GMC harmonic balancer is employed. This vibration damper is made up of two pieces attached together by rubber plugs, spring loaded friction discs, or both. As the power coming from the cylinder gets to the front of the crankshaft, it attempts to twist the harmonic balancer’s heavy portion. But it usually ends up twisting the discs or the rubber joining the two damper parts. The front portion of the crank can’t turn the way the damper did because the force is being consumed in twisting the rubber and speeding up the damper wheel. And this causes the calm operation of the crankshaft.

GMC harmonic balancer doesn’t just act upon vibration. It also helps in extending the service life of the engine by reducing wear on the main bearings and journals. Plus, GMC harmonic balancer helps in preventing defects and failure on the crankshaft. It is great preventative maintenance for your GMC vehicle to replace damaged and defective GMC harmonic balancer. So if ever you notice that your original GMC harmonic balancer is already defective, have it replaced immediately

Cross

iTrader: (10)

There is that much Vibration from the Crank?

Thanks for adding the extra information I am going over it now.

Hmm... with everything I have read all over the place going both ways esp the worn out rubber points brought up and evident in my stocker it makes me wonder still...

I guess its a good idea to buy another balancer and I might as well get a good one... for now I will bolt up that stocker thats not in great shape until it gets here.

Thanks for the info I have added it too my collection.