levelr123g

you can apply the same theories to any engine as every 4 stroke works exactly the same way, and every 2 stroke works exactly the same way. so until you can show me where they are different i can cross the engine types over.

ONCE AGAIN I ASK YOU TO SHOW ME ONE FAILURE DIRECTLY RELATED TO A CRANK PULLEY. YOU WILL NOT BE ABLE TO.

mdp c230k

Buellwinkle, I am going to do something about it. My birthday present to myself is a ring which I will put a couple small spot welds on to couple it to the pulley. This should happen around the middle of next month. Since the pulley ring is around the rotational axis it will not change the dynamic balance. You might notice that the people that agree with me are the ones with jobs in fields that are directly related to engineering. I hope that you never experience any problems as a result of your pulley but you are more likely to than you might want to believe.

vadim

Spot welding, ouch! Wouldn't it be better to use hi-temp glue? Or just use red locktite?

Buellwinkle

I still dissagree, welding the ring on will even further bring the pulley out of balance. Also it creates an issue of not being able to easily restore the car to stock should something happen. I sure hope your car doesn't develop any problems because of it.

Have you checked with MagnaSLK, I don't think he ever sold his brand new replacement ring so it may be cheap.

speedfrk

"you can apply the same theories to any engine as every 4 stroke works exactly the same way, and every 2 stroke works exactly the same way. so until you can show me where they are different i can cross the engine types over.

ONCE AGAIN I ASK YOU TO SHOW ME ONE FAILURE DIRECTLY RELATED TO A CRANK PULLEY. YOU WILL NOT BE ABLE TO. "

V engines, flat engines, inline engines, radial engines, W engines, etc all work exactly the same? You know just enough to be dangerous. Dinan's paper was right on from an engineering standpoint. If you don't like what he said, you can choose to ignore anything you want, but you can't change physics.
Statistically, there are not enough pulleys on these cars to make any judgement about how safe they are. Just because one car has say 80,000 miles on it with no problems, doesn't mean others won't have problems at half that mileage. That's why manufacturers do millions of miles of testing, and keep very detailed records of warranty claims.

levelr123g

i know just enough do be dangerous?
obviously you dont realize that a 4 cycle engine whether it be an inline 4, inline 6, v8, v6, radial, single cylinder, 5 cylinder, 3 cylinder. they all work the same way. PERIOD!
all 2 stroke engines work the same way. PERIOD!

if harmonics are so detrimental then why dont the use a dampner on the cams? i mean with metal hitting metal this causes the metal to resonate, right? the cams should have the same problem as the crank, correct?

as far as the length of time pulleys have been on cars, they have been using pulleys for years on many cars and ive never heard horror stories of failures. if there are so many failures then where is the proof?

Still waiting.

speedfrk

If you mean they burn an air/fuel mixture in a cylinder, you are completely correct. Even bullets do that. That has nothing to do with crank or bearing failures, harmonics, torsional stress, and a host of other things you completely neglect and know nothing about. Every one of those engine types has a totally different crank and bearing configuration. You can't just make sweeping generalizations like you do and then end the sentence with "PERIOD". I spent 4 years at a pretty good engineering school and had the guy who designed the Chrysler slant six engine as my IC engine design professor. If you really want to understand this stuff, I can recommend a few good colleges, but it really is beyond the scope of a forum like this expain harmonics, stress paths, failure modes and all the other things involved. Just do what you want. If you want to put a pulley on, do it. I'm just putting some information and food for thought out for those who have concerns.

Buellwinkle

OK, how about the 6 cylinder Acura NSX, no harmonic balancer/damper in that motor and that's a high reving, high performance motor (like mine!). All that is definite about the Supra or Dinan articles is that you shouldn't use solid underdrive pulleys on these cars as they are prone to failure.

speedfrk

Straight sixes are probably the worst case because of the long crank. The NSX was also probably designed to not need a dampener, or they found during testing that it didn't need one. My feeling on the 2.3 MB engine is that it is there for a reason. But like I said, only the engineers at MB know exactly what that reason is. The engine may be so strong it will last forever without it, and it is just there for NVH reasons, but I wouldn't assume that especially if you haven't noticed any change in NVH with your alloy pulley. I don't know if Vaeth would tell you, but I bet they have some info on this that dictated their design. Still just guessing though.

levelr123g

so who was your professor
1:william weertman
2:don moore
3: fred rose
4: john hurst
5: ray latham
6: john plainer
7: bob rarey

so in one post you swear up and down that an engine needs a dampner due to harmonics and in the next post you say maybe they decided it didnt need one. which way is it? in dinans paper which you regard so highly, every engine should have this problem, correct? so in the high revving nsx engine it doesnt need one but in the 4 cylinder it does? so one engine produces such harmful harmonics and the other engine doesnt, or did they engineer around that problem? if you spent 4 years at an engineering school then you should have an answer.

speedfrk

The only thing I "swear" is that MB put that dampener on for a reason. Dinan gives a lot of good reasons why that might be so. Like I said all along, only MB knows why it is there. Just don't assume you can do away with it and not have problems. I just don't want other people to not have correct information before deciding on something like this. You can do whatever you like, but don't throw mis-information out that could mislead someone else.
And I honestly can't remember the Professors name-It was almost 25yrs ago.
Lets just agree to disagree at this point. You think the the dampener is useless, and I'm pretty sure MB put it on for a reason. This thing has been beat to death on this forum several times, so I'm done with it.

mdp c230k

The NSX engine uses titainium con rods and lightweight al alloy pistons that make the difference. Our engines do not benifit from these lightweight parts and as such put more force on the crank. That is part of the reason the NSX does without the balancer. One of the others is that in a 6 cyl engine there is a balance between the actions of all the pistons. This means that when two are up, two are down, and two in the middle of their cycles only on different strokes. This provides a unique balance in the forces on a 6 that others don't have. Our 4s have huge pistons and a good stroke that add up to vibration that the damper is there to absorb. Like Speedfrk said, enough said, we tried to give so important information so people could make informed choices. It is up to them whether they use it or not.

Buellwinkle

That's the most contradictory thing I've heard. You say a 6 cylinder is balanced when in fact all the crank failures you show us are on 6 cylinder cars (supras and bmws). This does not provide information, it provides confusion. Show us real live numbers either in the form of torsional vibration charts for the 2.3L or what's the most realistic measurement, actual mean time to failure numbers from cars using pulley kits vs. unmodified cars for the past 4/5 years. All you can produce in your theory is fear, uncertainty and doubt.

Meanwhile you drive around with Eibach sway bars that will surely get you killed when a wheel comes up off the ground on a mountain road and you skid aimlessly over the cliff! What will that do to your crankshaft?