Re: Under Drive Pulleys..and the problems they cause.
 

Once again in order to make those claims read what i posted. Take those steps, and then this claim can be rendered true. Not bashing on you in any way. :3amin: I just dont see the logic in what is being posted. I know Al and others explain it and have dealt with it, but its only theoretical at this point. Take the step and measures in analysis to determine what other factors contribute to this outcome of damaged gears. To the gentlemen who mentioned balancing and harmonics dont co exist with one another; Last time i checked it did:)

benefits of balancing from within benefits in reduced wear of components, reduce vibrations transmitted throughout an engine. Able to reduce the size and weight of components without any disastrous output. keep in mind on how i said disastrous not negative. It is still feasible to experience a negative output with any modification but disatrous? higly unlikeley unless you are incompetent.:claus:

Re: Under Drive Pulleys..and the problems they cause.
 

Have to warn you, this argument is about faith to most people vs proof. With that being said, it's akin to arguing which religion is better. There's no clear winner to the argument, only a bunch of pissed off people in the end.

Tony

Re: Under Drive Pulleys..and the problems they cause.
 

UDP = :mean!:

Re: Under Drive Pulleys..and the problems they cause.
 

http://www.corral.net/forums/search....archid=4216206

'Nuff said. :claus:

Re: Under Drive Pulleys..and the problems they cause.
 

The Corral is sloooooow. Its a link to numerous threads where Al comments on u/d dampers and stock oil pump gears.

One of the threads does include those pics, or at least did last time I read it. The posts are a few years old now.

Re: Under Drive Pulleys..and the problems they cause.
 

Nice find but still considered inconclusive. You understand why, right? and Voodoo..:smack:

Out of the thousands pumped out of production (cobras, machs and 2vs) how many have experienced this dilemma? what is the ratio of damaged to not damaged? what percentage had it on a drag application? etc etc. Its questions like these that'll help you determine or guesstimate a problem. It wont find the solution, but you'll be one step closer in getting your answer. And please stop with the he said she said. Its very childish and the "evidence" isnt detailed enough on ANY of those post. No matter who its from. Sorry.

Re: Under Drive Pulleys..and the problems they cause.
 

Inconclusive to you maybe, but to me there is a very clear trend.

Ford produced a unique damper for the 2000 Cobra R. With the 08 Bullitt, Ford decided to extend the rev range on that engine and they also felt the need to introduce another damper design with it. Ed Olin, one of the guys involved with the development of the 2000 Cobra R powerplant, made numerous posts on this very topic. The testing has been done, whether you choose to accept it or not is up to you.

Re: Under Drive Pulleys..and the problems they cause.
 

Seems like LXH89 was correct.:what: Where may i locate this "testing" analysis? As an engineer im sorry but i disagree with you. I have to look at things from a closer stand point. Im not your typical forum user who believes everything the gentlemen with 1k post has to say. Anyways, Thank you for the information you've provided.

Re: Under Drive Pulleys..and the problems they cause.
 

Look for posts by EDO (Ed Olin) on the Corral.

I'm not the type to believe whatever I read on a web forum either, in this instance the information provided is fairly convincing.

Re: Under Drive Pulleys..and the problems they cause.
 

yes i am familiar with vibrations or resonance transferred throughout an engine by a lack of Balancing and other alternatives as well. why? I believe these were internally balanced so an offset on external weight should not affect it. Not even by a fraction of a percentage.

Re: Under Drive Pulleys..and the problems they cause.
 

Thank you. I will see what this man has done to confirm this theory. I most likey will stop posting about this subject. its obvious its a lose lose situation no matter what the outcome or development of this is. Thank you all.

Re: Under Drive Pulleys..and the problems they cause.
 

With "internally balanced" engines, the counterweights themselves handle the job of offsetting the reciprocating mass of the pistons and rods. "Externally balanced" engines, on the other hand, have additional counterweights on the flywheel and/or harmonic damper to assist the crankshaft in maintaining balance. Some engines have to be externally balanced because there is not enough clearance inside the crankcase to handle counterweights of sufficient size to balance the engine. This is true of engines with longer strokes and/or large displacements.

When rebuilding an engine that is internally balanced, the flywheel and damper have no effect on engine balance and can be balanced separately. But with externally balanced engines, the flywheel and damper must be mounted on the crank prior to balancing.


:confused: :confused: :confused: lets lay this matter to rest. its heading no where.

Re: Under Drive Pulleys..and the problems they cause.
 

Im not trying to find a gap or alternative to turn this around on you but they each correspond to one another.

Re: Under Drive Pulleys..and the problems they cause.
 

Engine balance is the design, construction and tuning of an engine to run smoothly. Engine balance reduces vibration and other stresses, and may improve the performance, efficiency, cost of ownership and reliability of the engine, as well as reducing the stress on other machinery and people near the engine. therefore, it being internally balanced and a weight difference if a pulley swap should not have any affect on this mechanism.

Re: Under Drive Pulleys..and the problems they cause.
 

Do you understand that the harmonic damper on a Modular engine, or any internally balanced engine, does not contribute to balance? These dampers and flywheels are nuetral (zero) balance.

Re: Under Drive Pulleys..and the problems they cause.
 

Yes. Just some food for thought.


Torsional vibration is a concern in the crankshafts of internal combustion engines because of several factors.

Alternating torques are generated by the slider-crank mechanism of the crankshaft, connecting rod, and piston.
The motion of the piston mass and connecting rod mass generate alternating torques often referred to as "inertia" torques
The cylinder pressure due to combustion is not constant through the combustion cycle.
The slider-crank mechanism does not output a smooth torque even if the pressure is constant (e.g. at Top Dead Center there is no torque generated)
Engines with several cylinders can have very flexible crankshafts due to their long length.
There is inherently little damping in a crankshaft to reduce the vibration
If torsional vibration is not controlled in a crankshaft it can cause failure of the crankshaft or any accessories that are being driven by the crankshaft (typically at the front of the engine, the inertia of the flywheel normally reduces the motion at the rear of the engine).

This potentially damaging vibration is often controlled by a torsional damper that is located at the front nose of the crankshaft (in automobiles it is often integrated into the front pulley). There are two main types of torsional dampers.


Tuned absorber type of "dampers" often referred to as a harmonic dampers or harmonic balancers (even though it technically does not dampen or balance the crankshaft). This damper uses a spring element (often rubber in automobile engines) and an inertia ring that is typically tuned to the first torsional natural frequency of the crankshaft. This type of damper reduces the vibration at specific engine speeds when an excitation torque excites the first natural frequency of the crankshaft, but not at other speeds.

Over time, the energy dissipating (rubber/clutch/fluid) element can deteriorate from age, heat, cold, or exposure to oil or chemicals. Unless rebuilt or replaced, this can cause the crankshaft to develop cracks, resulting in crankshaft failure. (have these ever been looked into as a factor?)

Re: Under Drive Pulleys..and the problems they cause.
 

In what shape or form? i cut and paste from reliable sources (i'd be glad to give you all the information you want such as web addresses and such) so those that are ill-informed to further read up on the matter and subject to gather enough detail and information to come up with a logical explanation of things. This has been carried far enough. A man of your logic id expect YOU to reason and understand that a guess is a guess and there is no EVIDENCE that can attribute to these losses. Once again this has been proven to be a "religious battle" and i refuse to continue and i'll let you all wither away with this false assumption. Thank you once again M1M and all of you who participated in posting YOUR belief.

Re: Under Drive Pulleys..and the problems they cause.
 

M1M if you (or anybody) can somehow manage to solve this by adapting these formulas to calculate the output of amplitude through a crank. I'd be more than happy to oblige to these statements you hold on to dearly. :smokin: This all can be done with exact measurements of the 2 different pulleys that are in question. Gather spec info like weight, size etc etc. these here have to be considered and nearly each one has its formula. The output has to be either identical or close to as factory specifications.

Center frequency
Driven harmonic motion
Formant
Harmonic oscillator
Impedance
Q factor
Resonator
Vibration
Schumann resonance
Simple harmonic motion
Tuned circuit
Wave
Sympathetic string

Re: Under Drive Pulleys..and the problems they cause.
 

And im done:3b: its bad enough i do this on a daily basis and now i have to discuss this process with one of my favorite hobbies. Oh brother. makes it less enjoyable. lol..whos the little kid?

Re: Under Drive Pulleys..and the problems they cause.
 

So I guess if someone puts a bullet in your brain but doesn't fully comprehend the muzzle velocity, ballistic coefficient, density of bone vs. lead and the full biologic effect of head wound then you won't be dead?


If you guys want to debate the science, go ahead. We have some real-world empirical evidence that has convince the majority of car nuts on this site. Even I've gotten enough data to believe that the combination of a smaller balancer with our crappy oil pump gears is a bad combination (especially for manual trannys without the torque converter to help dampen the issue) and I'm the guy with over 100K miles on SLP 2-valve pulleys.

If you don't want to believe it without a scientific explanation, to ahead and play russian roulette with your motor. I'm sure if the oil pump grenades we'll never hear about it.

Re: Under Drive Pulleys..and the problems they cause.
 

Let's have a drink to the flat earth society. I'll send you all some post cards in my travels around this spherical earth.

Signed,
Columbus

lol.. I couldnt resist...

Tony

Re: Under Drive Pulleys..and the problems they cause.
 

do whatever the hell you want and in a few weeks we'll see one of those "wtf, my motor sneezed and locked up" threads...

Re: Under Drive Pulleys..and the problems they cause.
 

Look, all i ask for is substantial evidence that has been documented! Before a conclusion can be drawn you must evaluate its findings! why is that hard to comprehend here? read this and maybe you'll understand what i mean.

Scientific method refers to the body of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge. It is based on gathering observable, empirical and measurable evidence subject to specific principles of reasoning. A scientific method consists of the collection of data through observation and experimentation, and the formulation and testing of hypotheses.

Although procedures vary from one field of inquiry to another, identifiable features distinguish scientific inquiry from other methodologies of knowledge. Scientific researchers propose hypotheses as explanations of phenomena, and design experimental studies to test these hypotheses. These steps must be repeatable in order to predict dependably any future results. Theories that encompass wider domains of inquiry may bind many hypotheses together in a coherent structure. This in turn may help form new hypotheses or place groups of hypotheses into context.

Among other facets shared by the various fields of inquiry is the conviction that the process must be objective to reduce a biased interpretation of the results. Another basic expectation is to document, archive and share all data and methodology so it is available for careful scrutiny by other scientists, thereby allowing other researchers the opportunity to verify results by attempting to reproduce them. This practice, called full disclosure, also allows statistical measures of the reliability of these data to be established.

This is only one of the many methods I use to find things unequivocal.

In some weird way there is a resemblance here with animal farm. Some of you are easily convinced and believe everything you read. With not one person looking for an alternative to this "dilemma". It shows lack of intellect and the lack to see if there is more than 1 answer. Im done. Theres no point in arguing with any of you people because it doesnt get us any closer to our destination. So i stand by and say "this is still in the beginning stages and needs to be confirmed with testing, reliability, and reporting." have a good day to those with and without UDP's and do as you please.

Re: Under Drive Pulleys..and the problems they cause.
 

:CHEERS: seriously my last post on this matter. lmao

Re: Under Drive Pulleys..and the problems they cause.
 

:23: :23: :23: ignorance is bliss huh

Re: Under Drive Pulleys..and the problems they cause.
 

Well professor, there is an alternative. In fact there are several.

Don't use smaller, aftermarket balancers.
Replace your oil pump gears with billet.
Do both.

I have opinions from well-known engine builders and from a product manager at Ford that broken oil pump gears are a problem, both with OE and aftermarket balancers. Smaller diameter balancers are believed to increase the risk somewhat. That's far from what I would consider an ignorant stance. In fact I'd consider it a well-informed perspective.

I don't have full engineering and testing data. But I don't have that for any other mod I put on the car either. I just use what seems to work for people whose opinion I respect. As far as I'm concerned, expecting a consumer to require this kind of data before making a purchase is rediculous.

Re: Under Drive Pulleys..and the problems they cause.
 

"Now on to the next topic of discussion, I want to tell you all about the Tornado Air. According to a well known mechanic named Sam Memmolo, co-host of Two Guys Garage, he supports the product. Clearly this is an indication of the validity and worthiness of the product.

Also, please don't complicate this discussion with statistics or request of any demonstrable proof. That's quite ridiculous because you would be questioning the word of a highly respected mechanic who has his own TV show. Surely one wouldn't be that bold? Think about all the kind folks that Sam has helped over the years with their car troubles. You might hurt Sam's feelings and he'll stop his TV show and won't help us with our problems any more--only a b@stard would try such a thing! Have I mentioned only a fool would question Sam? Oh yes I did, anyways...

In addition to that supporting evidence, I also offer further proof whereby the product was tested at a CARB recognized lab demonstrating an average increase of 1 to 2mpg. Again, please don't question the test methods because you would be questioning the results from a CARB recognized lab. Only a fool would do that!

Also, did I mention Sam's a great guy and would help anyone? Only a jerk would question him. We all know he's got more knowledge in one hair folicle than the sum of all people who ever lived aggregated and multiplied by a factor of 1,000,000. Therefore questioning Sam's opinion is a sure sign of how feeble minded you are. But anyways, back to the topic...."

In all seriousness, that characterization very well represents some of the positions I have seen taken on this topic. As ridiculous as the above scenario sounds, there are many parallels to some of the arguments I've seen made on the topic of underdrive pullies.

Tony

Re: Under Drive Pulleys..and the problems they cause.
 

The determining factor between the science versus real-life arguement is that science does not use rev-happy, crappy drivers as test subjects, but rather assumes the drivers are perfectly nutty old men and lead-footed youngsters(I) who bought this car to push it to the limits. The engine is built with that in mind, and an attempt to disrupt how the internals function is plain ol' stupid.

Re: Under Drive Pulleys..and the problems they cause.
 

Underdrive pullies are bad enough sad!



LS

Re: Under Drive Pulleys..and the problems they cause.
 

Alright, now that I posted my fictional exchange about the Tornado Air. Here's the thread from July of 2006 where I was burned at the stake on the corral for calling Underdrive pullies being responsible for oil pump gear failure an Internet Myth. Boy was it a fun exchange...

http://www.corral.net/forums/showthr...=internet+myth

It's funny how history repeats itself, eh? Humans are definitely creatures of habit... lol

Tony

Re: Under Drive Pulleys..and the problems they cause.
 

I sat and absorbed every page of information on that forum and yet they gave you the same lame excuse with no proof (oh theres that word again). The answers that were drawn up were just sad. Especially coming from a well known "respected" engine builder.

You bestow a solid point LXH89 with that fictional story you posted. Makes you wonder, right?

"An engineer speculating without having definitive proof and testing to corroborate is no better than my grandma speculating as to the cause. Sure, it's probable but no reason to throw it out like it's fact." :LAUGH:

This is exactly why it shouldn't be considered a valid statement.

Re: Under Drive Pulleys..and the problems they cause.
 

Lets not get violent now fellas. This is only a dispute. I believe we've evolved and learned how to communicate efficiently without disregard towards one another, right?

Re: Under Drive Pulleys..and the problems they cause.
 

Bill's a good guy. He's smart enough to recognize the points being made. I know he's teasing... he likes stirring the pot to see what happens for entertainment.

I mean, don't those Naval nuclear engineers have to be smart? Don't hold it against him that at night time he glows. It's not his fault.. :)

Tony

Re: Under Drive Pulleys..and the problems they cause.
 

okay.

Re: Under Drive Pulleys..and the problems they cause.
 

:12: ...lol

Re: Under Drive Pulleys..and the problems they cause.
 

you been smokin killer dro? :smokin: :23:

Re: Under Drive Pulleys..and the problems they cause.
 

The only reason anyone would argue the case for underdrive pulleys is if they got off on arguing for the sake of arguing or, if they or someone they know has a vested financial interest. Nobody here has the time, resources or desire to put a set of pullies through a 10 point failure analysy. Making decisions without knowing every detail is what grown ups have to do every day. We cant be experts in every field so we rely on experts.

People have measured Steeda pullies and found them to be out of round. People have swapped from Steeda's to other brands and noticed reduced vibration from the engine. And Steeda underdrive pulleys have been the most logical culprit in a series of oil pump failures. Anybody who needs a 10 point failure analysys to disuade them from using Steedas has been hit one to many times with the stupid stick.

Were not sending men to the moon, were simply trying to decide if an extra 5 horsepower is worth risking the destruction or our engine when several comparable, but clearly safe options exist. Do we REALLY need to build a case defending Steeda pullies?

Todd

Re: Under Drive Pulleys..and the problems they cause.
 

Doesn't he get paid to make that show? And wouldn't somebody benefit from paying him to say something works, whether it did or not? Some people like to watch those TV evangelicals too, send us your money and we'll make sure you get into heaven... I don't believe them either... Maybe i'm the fool :soapbox:

Re: Under Drive Pulleys..and the problems they cause.
 

I know this is a little late in posting... but this is a subject I've done a LOT of research on.

...and I have a very simple answer to why you don't hear much about the negatives of UD pulleys.

So many people swear by them, just like people swear by K&N, etc... but how often do you hear anything negative about them? And for the negative side effects, why don't you hear much about the negatives?

Because people spend a lot of money on such small mods, they don't want to openly admit they made a bad choice. Case in point: My K&N SUCKS. Literally and figuratively. It's not the best aftermarket CAI you can buy. I immediately started experiencing issues with stalling after installing it. Some other forum members here have talked about it. But I'm certain there are a larger number of people out there that refuse to say anything bad about it. They'll swear by it, knowing full well they've purchased garbage, just as I have.

As for the positives mentioned... ironically, the only things I see are an occasional honest opinion about how much of a gain someone got out of the install. And of course the unGodly amount of blasphemous overexaggerations of gains that only a supercharger install could rival.

Even with other bolt-ons, I'm sorry, but the gains aren't going to be multiplied. An intake spacer gaining you 4 HP isn't going to multiply your 3 HP gain from UD pulleys to 12 HP. You might get 7, and woohoo.

People are entirely too stubborn to admit that some things simply aren't worth it. Since they've spent money on it, they try to convince other people to spend money on it. If someone duped you into spending $300 on a bag of garbage, I'm sure you'd feel better about yourself if someone else did the same thing. I know I'd be thinking, "Thank God I'm not the only one in the world who made a bad choice."

Bottom line... a lot of the people on this forum have been at this with these particular cars since they first started shipping 'em out over 5 years ago. If they advise against doing something to it, I'm pretty sure their level of experiences with these matters is worth taking into serious consideration over false "scientific" statistics (due to consumer misinformation based on shame).