Unorthodox Crank Pully - Unsafe?

[Red Recluse]

I got a full pullykit from Unorthodox, and I was told that since the crank pulley doesnt have any kind of a bushing/bearing on it (forgot specific name used) that I'll hear and feel a lot of engine noise, and could possibly damage the crank??

 

[Red97Eclipseboy]

It doesn't come with a harmonic balancer. The best way to use one would be to have your rotating assembly balanced first.

 

[DGajre777]

It doesn't come with a harmonic balancer. The best way to use one would be to have your rotating assembly balanced first.

I agree with Red97Eclipseboy. If you don't want to have your rotating assembly balanced (for whatever reason), but still want a light weight underdrive crank pulley, you can get one that has a built-in harmonic balancer. Extreme motorsports sells one for $348. I wouldn't recommend putting the underdrive pulley that you have.

This is what the description states on their website: CNC Billet Racing Damper. This harmonic damper also works as a underdrive pulley thats helps increase usable horsepower while protecting your engine. They are hard-anodized for durability and are a direct bolt-on. The 4G63 is an inline four that is susceptible to harmonic resonation, especially at high RPMs and in race applications.

Check out their website if you are interested - http://store.extrememotorsports.com

 

[Defiant]

A harmonic balancer isn't for "balancing" anything other than crank windup. It's not for balancing the bottom end.

 

[Boiler2]

I have been running the Unorthodox full set for 2 years now with no ill effects. My charging voltage is a little lower though. I too have read all this info on a number of different sites and have been waiting for something to go wrong with my crank. I am about due for a timing belt change and was planning to get the one from Buschur which has a dampener. I have not noticed that much of an increase in power. I have not dynoed anything but at the track, driving ability weighs in more important than adding an underdrive pulley.

Before I got the set from Unorthodox, I wrote them for a response on the lack of a dampener and its possible ill effects. They responded stating that there is no proof and that many cars run without one and they have had a number of satisfied customers, blah blah.

Oh yeah, when installed, your car will run smoother, not rougher like you heard.

 

[Red97Eclipseboy]

A harmonic balancer isn't for "balancing" anything other than crank windup. It's not for balancing the bottom end.

I never said it was. Just after research and talking to many well-known DSM shops, that's what everyone of them said.

 

[Erik95GSX]

Hey whats up my friend has the full set in his 97 tsi and has had no problems engine runs a lot smoother but nothing has gone wrong but he didn't notice any difference.

 

[heavypedalmuzic]

i took my underdruve pulley off due to low voltage + i was a little concerned about it not having a harmonic balancer. i replaced it with a stock one, regained my voltage and notice no change in performance. though i must state i did not dyno the car before and after. though i have a friend that had bearing problems 3 times until he removed his...since that no bearing problems, could be coincidence but take it for what its worth.

 

[Hammer_Gaidin]

The advantage to the UR set is that it ends up having less rotational mass. Thus, you should gain acceleration, however loose tourqe. I have a set on my gst and like it. I didn't notice any negative effects. As for positive effects, it would have been hard to tell since i did a lot of upgrades at once. However, I notice that my car runs smoother with the UR pulleys than stock, and that my rpms rev fast, hense less rotational mass.

I'd say put them on .

 

[Red Recluse]

Thanks for the help ya'll... They sent me the set as part of the contract agreement and heard a few ill things... I'll put them on when new motor comes in ....damn rods.

 

[Defiant]

The advantage to the UR set is that it ends up having less rotational mass.

You have reduced leverage on the pulleys from the smaller diameter. The amount of mass reduced is trivial.

Thus, you should gain acceleration, however lose tourqe.

Uh... what? How?

 

[Hammer_Gaidin]

You have reduced leverage on the pulleys from the smaller diameter. The amount of mass reduced is trivial.Uh... what? How?

The set of Ur pulleys that I recieved were exactly the same diameter as the stock. The fact that you gain acceleration is due to the smaller rotational mass. The engine can rev faster because the motor has less to spin. And you would loose torque because of the inertia. The lower the inertia the less tourqe, because not only does loosing weight help you gain acc, it also lets you dec faster, hense the loss of tourqe. But the loss would only be a few points. Really it is lowering the "flywheel effect," in all actuality. The same thing happens when you go from a heavier flywheel to say an 8lb one.
Sorry if the explaination is confusing....hard to put into words.

 

[SethA]

I believe Hammer is confusing torque and inertia. Power is the product of torque and RPM and a contant. More power means more torque always. An object with large inertia will want to stay at the same speed. The underdrive pulleys he is referring to would have less inertia and therefore accelerate and delerate more quickly than non underdrive pulleys.

I have never heard of only lightened pulleys. The primary gain in underdrive pulleys is the "underdrive" effect, hence the name.

Seth

 

[Hammer_Gaidin]

If i am wrong, i appoligize. Just from my understanding, well i know tourque is the amount of force over a distance. And I just figure that since the inertia from the extra rotational mass assists the spinning motor, more than a pulley that weighs less, the tourque would be lowered. Once again though, if i'm wrong i appoligize.

But all and all...pulleys=good

I bought my set from Extreme Motorsports. I got the entire SS set, and all of the pulleys were the same size as the stockers, except for the fact that they were Xtimes lighter.
Less rotational mass=awesome

By the way, i'm Seth too...two Seth's driving dsms...it must be fate.

 

[xveganxcowboyx]

I have never heard of only lightened pulleys. The primary gain in underdrive pulleys is the "underdrive" effect, hence the name.

Seth

I was under the impression that the underdrive effect only yielded about 15% of the actual power gains and that the lightening was where the rest came from.

Either way I think there are better ways to make power, but I never understood the underdrive effect if it didn't yield much. Why not just go with stock size, but lighter material?

 

[SethA]

I hardly ever meet another Seth, let alone a DSM Seth. Way Cool!

Seth

 

[boostedinaz]

Like it has been pointed out many times before the pulley is a HARMONIC DAMPNER not balancer. I bet if you asked any of these performance shops how exactly a dampner works you would get a weird look for a bit. I didnt even know how theyworked until a bit ago when I read a great article in Car Carft about them and how they are beneficial and add to the longevity of a motor.

The easiest way to explain this to look a the pedals of a bike. When you push down on the pedal it will twist the crank, now this isnt like bending it, but a very minute twist. Now imagine this on a crank, swinging rods and pistons at 8500 RPM, and you can bet that twist is a bit more. The dampner helps to keep that twist to a minimum and keep and "feelings" of that twist from Joe Consumer while he drives to work by absorbing it. When you get rid of the dampner you dont have anythign to combat this. Now you can always go with the ever popular DSM reason of, "So and So has done it for months with no problems," but ignorance is an excuse not a reason.

 

[Defiant]

(dampener)

 

[doug]

I've mentioned this in several other threads, so hey, what's one more. I've personally put about 60K miles on my one-piece pulley and am still loving it. However, DO NOT install one if your only goal is HP-- the gains are negligible at best. The main reason, IMO, is to eliminate the possibility of the stock pulley failing (coming apart into two pieces) and possibly messing up the engine pretty bad. From what I've found, stock pulley failure seems to be a more common occurrence than mysterious bearing wear or whatever from a non-dampened pulley. Am I saying that the warnings about one-piece pulleys are unwarranted? No, but I'm not convinced yet, either.