mrz udp

[andrew383]

i have one,does anyone else? how do you like it? good bad and the ugly

[3100 MPFI]

don't have one, and you can't pay me enough to use one. Those don't have the rubber ring to cancel out resonation. Only a matter of time before the engine blows up.

[loner666]

ive got one..no problems yet but hasnt been on long

installed it with alot of other stuff so i dont know if there was a difference

3100MPFI: if you email them i bet they will make you one with a rubber ring in it or make it so one can be put in

[3100 MPFI]

last time I asked them about it, they said that no they would not seeing the wanted it out to help with the weight savings. They also said something about it not being for all the time use, and RACE ONLY, so most people would not be stupid enough to keep it on their cars (knowing that it does not include the harmonic damper).

That left a bad taste in my mouth. I have put too much time, money, and effort into my engines to let them blow up using a product that is not designed to reduce the risk of damage.

[19Cutlass94]

After having a UDP on my 3100, Ill never use one again. Once I take out the engine, that UDP is for sale.

[El_Diablo]

if you have a balanced engine it'll make no difference, there are more than a few guys running them (udp's in general) without issue

[3100 MPFI]

if you have a balanced engine it'll make no difference, there are more than a few guys running them (udp's in general) without issue

I highly recommend you reading this.

http://en.wikipedia.org/wiki/Harmonic_balancer

By not having the rubber ring to cancel out RESONANCE (which puts more stress on the crankshaft that it can handle), your engine becomes a ticking timebomb.

If you use an UDP that does NOT have a harmonic damper, then it is not a matter of IF your engine blows up. It is a matter of WHEN.

[sprucegagt]

I highly recommend you reading this.

http://en.wikipedia.org/wiki/Harmonic_balancer

By not having the rubber ring to cancel out RESONANCE (which puts more stress on the crankshaft that it can handle), your engine becomes a ticking timebomb.

If you use an UDP that does NOT have a harmonic damper, then it is not a matter of IF your engine blows up. It is a matter of WHEN.

I'll let you know when my engine blows up. 132,000+ miles of which the last 50,000 have been with a crank UDP. Personally I think operating RPM plays a key part in resonance failures, namely high RPM say above 5,000.

[El_Diablo]

our engines are internally balanced and therefor do not use a harmonic balancer, in fact a harmonic balancer and harmonic damper are not the same thing at all contrary to what is stated in that wiki

i'll state it again, an internally balanced engine DOES NOT, need a balancer and will usually do just fine without a damper, i myself have yet to see a 660 crank that, shall we say, "blew up" due to a UDP being installed

if you have such a problem its most likely that your crank already had a fatal flaw (aka a crack) of some sort from the factory or developed one through its life

[34blazer]

all engines need some sort of a harmonic dampener. even tho an engine is internally balanced, doesnt mean that its perfectly balanced. i.e. an inline 6 cyl has a perfect balance theorectically, but thats if its running absolutly perfect. even then it will have undesirable harmonics, if not cancelled out, could destroy the engine. theorectically, a 660 has a mild secondary inbalance which IS noticable. therefor, to sustain the reliability of any engine, a harmonic dampener MUST be used.

[geldartb]

what the hell is this rubber ring you speak of. every crank pulley from a stock engine hasnt had one. the only thing it has it the metal ring you transfer over.

[bszopi]

The rubber ring is embedded inside the damper. You can see it if you look. I'll try to find a picture.

[IsaacHayes]

Rubber between the 2 pieces.

[geldartb]

oh ok never really looked at that side.
ok if thats there for a reason on the stock one then why when they made the ud pulleys didnt they incorporate it into them.

[geoffinbc]

I think the biggest thing is people are confusing is balance with dampening. Yes the 660 is internally balanced. It is almost perfect. A 60 Degree V6 produces a primary and secondary rotating couple. The primary couple is simply balanced out with counterweights at the ends of the crank. The secondary couple only amounts to about 220LBs/ft at 4000rpm so it is not noticeable. And is left alone. A 90* V6 produces such a large secondary rotating couple that it is noticeable and most use a balance shaft to cancel it out. In case people are wondering this force is never balanced it still exists on the internal parts but the balance shaft masks it. So if you don't care about smoothness then ditch your balance shafts.

Anyways onto the the real function of the damper. Don't visualize a crank from the side. Visualize it from the end. Staring at the damper. Off of the center comes each crank throw and of course off of that comes the rods and pistons. Every time a piston fires it produces a huge force that pushes down on the crank throw and this forces is transfered to the center of the crank creating a twisting motion on the center of the crank. This force winds up the crank like a spring and the crank fights back by returning to its natural state. Now imaging just this one springing motion on every throw times 6 throws several times each second. All of this causes vibration in the crankshaft, completely independent of the pistons and rods, but around its axis. There is only 1 way to take care of these forces and that is with something to absorb them and transform them to something harmless. In this case, heat. That is the job of the damper.

So what happens without a damper? Well your crank bearings will not suffer like many think. What does suffer is rod bearings, piston pins, timing chains, valvetrain components and distributor gears.

You will not find a single car manufactured without one. You will also find the same is true for any form of endurance racing. Drag racers get away without one because the engine is usually built to mammoth proportions and the engine is looked at after every run.

Yea your street engine might last a good while without one. But you wont ever notice a problem until these forces do enough damage to push things beyond specifications where enough slop exists to cause a noise. Plus if you chug along around 2000RPM and never really work the engine hard then you may not arrive at these damaging results quite as fast.

The last benefit of a damper is POWER. Since having one dramatically improves smoothness in the valvetrain and distributor (if you have one) resulting is more accurate valve and ignition timing. I have never herd of anyone on this site reporting power gains from the UDP maybe the above is an answer as to why?