TCpete

you know what sucks about this...that people take the advice FROM REAL PROFESSIONALS AND ROAD RACING CHAMPIONS LIKE A GRAIN OF SALT...

this is why i hate scion life because its basically full of non hardcore performance, all flash no go and ricey people that when REAL hardcore performance PEOPLE step up to share their eperience and knowledge talk & actually try to help others get shot down themselves by young noobs who dont know jack about motors, racing, or have any real experience, or are just stuck in the slow lane of ricer mods that typically scion has been marketed for "that crowd"

i think you small timers need to learn to respect and appreciate PEOPLE WHO ARE ACTUALLY MAKING A DIFFERENCE FOR SCION AND PEOPLE WHO ARE ACTUALLY MAKING A RACE CAR AND DOING BIG THINGS TO PUSH SCION FROM A GIRLY CHICK CAR TO AN ACTUAL PERFORMANCE CAR THAT APOSES A THREAT TO OTHERS and not your led, over weight, slow, show crap 2/3/4/5 etc tone garbage cars you typically see the tc played as...

im probably one of the few on here also that is hardcore enough to build my own motor with my own hands from the ground up and im using a crank pulley and i RAG MY CAR TILL DEATH and nothing... my motor still holds strong and even when i took apart my old block i had 21k HARD miles on it with an aftermarket pulley for a good 21k (3 weeks into the car it was the first thing i got and guess what.. IT WAS CLEAN AS A WHITSTLE and no signs of engine wear, bearing loss, etc etc etc even the seals for the crank output were clean but hey what do i know ive only built 2 tc heads that made power and 1 high compression block and making numbres people on here SAID WOULD NEVER HAPPEN with out some NOS on an NA motor..

i think alot of this community should sit down and put their showcar ego aside and maybe listen to real world pros who actually have accomplished more then just winning a trophy for most riced out scion at your local car show..

Dan (adg016 ) it would be a loss to the boards if you did not post and even though this board is infested with this kind of immature and closeminded attitude i sincerely hope you press on with your findings and contributions to the scion community as there are HARD CORE ppl on here.. it may be harder to find them but they do exist.. sadly though it will take some time before that kind of close minded infestation will be weeded out of here..(highly doubt it anytime soon)..

please stay on the boards and just ignore the ignoraneces of common youth.. it would be a shame to loose good people because of the rudundant bunch.

tC9o9

this is not the first time dan has been shut down pete, he is through with this site..

people have no respect for real race cars, they are all into SHOW cars as you said.. if i were to make a thread, show your tC in action, alomst 9/10 post would be of it on a show floor, we would be lucky to see one on a track.

its okay tho, dan isnt the one who will be suffering a loss, its the whole scion community who will.

the ONLY way people can TRULY find out if a part works or not is TRIAL AND ERROR, not some stupid physics test.. physics isnt always correct, real testing done on track is what counts.

athletefeet66

iTrader: (1)

wow. i started some sort of feud i guess. thanks for all the feedback though. sorry if it has been discussed before i didnt find it.

i will trust the hardcore racers. thanks alot.

no more feedback is necessary unless you want to fight some more...whatever. i just want to drive a little faster

Sly_dawg19

Anybody who calls a toyota engineer knows that the "dampened pulley" is for noise vibration and harshness only. I.E. In cabin noise.

Everything toyota does is for comfort and mileage.

heavier crank pulley means more rotational mass to keep the car moving.

efigneer (i know i misspelled it) and countless others argued with me for 5 pages on how dumb I was for using a perrin pulley in my xA.

You guys are totally right, and opened my eyes a little wider, this site has revoked and persecuted the test track and road racing proven reults with theories and physics that dont measure up to real world testing results.

i just have one big great sigh for newbies on here learning from false teachings...

Just go out and drive, and try things, if it breaks try something else, forget what people say on here about anything, there is to much BS to filter out factual good knowledge.

just my .02

mattvs

I'll take the words of people with PhD's over some thumb-twiddling ____ on an internet forum.

Poor...Dan? Poor Dan gets shut down. Cry me a river, build me a bridge, and go jump off it.

tC9o9

if you want to stay closed minded thats fine.

Sly_dawg19

You know there was a time where doctors had certain brand of ciggaretes they recommended to people because they thought it was healthy.

There was also a time where doctors used to use leeches to suck out bad blood.

There was also a time where doctors used sugar as medicine.

Let me hit you up with some real facts here ok, Mr. X could have a Ph. D in physics, motion and heat transfer, alloys, mechanics, etc.. And not know a thing about cars over most of the general population.

Just because someone has a degree for one thing, doesnt make them the foremost authority over another.

Go to any college or university in the world and tell me if there is a "Toyota Crank Pulley Neccesities" class. I can garuntee you wont find one. So anythiing these Ph. D's say about the pulley is from information they received from someone else, or from self expirence on them. BUT if you search owners with crank pulleys there has been 0 failures due to the "non-dampened" crank pulley. So these Ph D's get information from others, which is highly uncredible compared to real life results.

You go ahead and smoke that healthy brand, get weekly leechings, and get your sugar fix. I will stick with what has been proven with concrete facts, not theoritical farsees.

TCpete

lolol

funny by looking @ your sig your riding in an evo now.. so let me ask you this does AMS which on the average build 500+ evo's hell they even have a few 800 and 900 hp street car evos build their car to mitsubishi's specs?? do you think companies like AMS listen to mitsubishi and have their "PhD's in motors" also but yet they walk away with on average 5-600 hp evos on the daily and the cars are very realiable if not more reliable then when they came out from OEM lol.. hmm ok but hey what do a bunch of knuckle head non PdD guys who build some of the highest performance parts or cars for the evo world know right?? lol

and let me ask you this.. how far did you get with your tc?? before you had to go to another company to go on boost and be faster?? probably not to far i would asume...but hey what do people like me know about motors also.. im just a art director for an ad agency who bleeds motor oil 24/7 and builds motors for friends as a hobby from hondas to now tc motors making more power NA then what toyota or what close minded people that thought the tc motor could never make or atleast was originally designed for making.. guess ill have to wait for that PhD degree some day.

kungpaosamuraiii

A random PhD in physics and the like won't know anything about what Toyota does and why Toyota does it.

And for the record, yes, the damper is made to dampen NVH and discomforting noises and stuff that come from the engine. Without the damper inside the cabin should feel a little more noise and vibration and harshness. The pulley is used to dampen NVH. YES.

However Toyco puts what they call "dual mode dampers" in their cars.

The other mode dampens torsional vibrations. It's there and it happens and the damper is used to dampen it. There is simply no way an engine can run without creating torsional vibration. And as such, the following pictures doesn't relate to any one car specifically, but to all Toyotas. In fact, it's called the


And page 12 talks about the dual mode damper and how it reduces cabin noise and dampens torsional vibrations.



See that the crank shaft twists with every cylinder firing. That makes sense and is something we all knew but note that the firings create a sinusoidal wave. And with waves, harmonics, with harmonics, natural frequencies, and with those, chaos. I'm not going to go back over natural or resonant frequencies again.

There is your proof. It's from Toyota; it's not from some dumb tuner like, what, Dinan, right? Sure, it's engine theory but it's from the guys who made the engine. But honestly, all this information has been hashed over and over again and no one has said anything new. In fact, that last sentence is almost verbatim what I've said before. I think this is all we need:

Take experimental over theoretical or theoretical over experimental. Experimental sounds good and all since it's real world data but if theoretical does not match experimental, either something is just waiting to happen or evidence that more studying needs to be done.

Ultimately we should just make people choose between whether
A.) something bad is going to happen and to not get the pulley
B.) current theory is wrong, some phenomen exists that makes pullies safe, and to get a pulley.

Honestly for me, there needs to be an explanation before I put it in my car. If for some reason the pulley will not cause catastrophe, I want to know why not and for sure why not before I put one on.

And for the record, leeches are still medically used along with maggots and the like. Glucose is often mixed with medicines and are infused into patients who can't eat. But yea, glucose and leech use in medicine has been greatly evolved. Cigarettes... closest thing is a medicinal joint. But yea.

Sly_dawg19

its funny and sad at the same time.

there is about 50% who support pulleys,

and about 50% who don't

these threads are like beating a dead horse. lol...

Ted7rnsRacing

There’s no need to argue who’s right and who’s wrong. We (Jackson-Dawson Team Scion) are here to develop a Scion tC race car and to win a National Championship in Performance Touring. We’re trying to Win, not to prove anyone wrong. Using smaller pulleys is part of this plan.

Now I understand what’s being said about the pulleys, it was also been said with other newer designed 4 cylinder motors as well. But, since we’re running the motor at limits and at redline every shift if something is going to go wrong it will happen on the track. We’re confident that no damage will come of it. If we weren‘t confident we wouldn’t be doing it. There's too much at stake here for us to make mistakes.

Now, Dan is not the only one working on this project (tC Race car), We have a lot of people with a lot of racing experience working on this project. We’re not some fly by night tuner, we are a factory supported race team with big goals to achieve. We have some great racing engineers, race car developers and crew members working on this project. We have higher goals then just winning a NASA National Championship in Performance Touring. We looking beyond that as well.

It's best for the Scion Community to support any and every Scion Race team. We all have the same love of the car. Race teams are the proven grounds for aftermarket parts. ScionLife will benefit from this race team.

tC9o9

well said Ted.. i hope we get as much support as possible and this thread or any other wont defer any one from supporting our team.

MotoIQ

From a lot of expeirance building actual racing engines, building winning racecars and building winning and reliable race cars I can tell you that a solid hub underdrive pulley is not likely to cause engine failure in a modern mildly modifed 4 cylinder engine.

My qualifications are that I was an engineer at TRD many years ago, I was an OEM engineer at Nissan spending the last several years working on the Nismo project and am now a motorsports engineering consultant. I have been an automotive and motorsports engineer for 20 years. I also happen to be a consultant for the Jackson Dawson team.

On a relatively understressed near stock motor like the TC with bolt ons or low amounts of boost like what we will be running and I suspect what most of the people on this forum probably run, an underdrive pulley will not have any life treatining consiqunces for your motors. The factory pulley with a twin ring damper is primarily for wide band NVH (noise vibration harshness) supression from the engine and driveline. Removing the damper and replacing it with a solid hub underdrive pulley will cause addtional NVH but not harm the engine.

The engineering reasons are that an inline 4 cylinder engine has a short stiff strong crank with a relativly high natural frequency. The dangerous second harmonic that can cause damage occurs at an rpm that this sort of engine will never see, in the area of 9500 rpm.

Now the stock harmonic balancer is not tuned for attinuation at this sort of rpm either so the argument is somewhat of a moot point.

Now 4 cylinders that are pushing the limit with lots of revs, wimpy cranks, super long strokes, lots of boost and dwelling in the upper rpm ranges for long periods of time can benifit from a damper designed to deal with this sort of operation but our engine is not like this due to rules contraints and probably very few people with this motor on this forum push the envelope that hard.

The tC engine has a strong and stiff bottom end that is overbuilt if anything for our intended use. It has an internaly balanced crankshaft, It has a chain driven oil pump which is less like to break due to torsional vibration like the more common crank snout driven georotor type found on Honda and Nissan motors. Nothing is going to happen, not even in our road raced tC. Road racing is much more punishing on an engine than other motorsports. The engine is subjected to run times lasting anywhere from 20 to 45 minutes with the engine always in the upper ranges of its rpm limit. One race weekend is the equivlent of hundreds of 1/4 mile passes.

Some engines like the Nissan SR20 have to have an underdrive pulley to live at all under race condtions as the water pump cavitates at a low rpm. All SE-R Cup cars and probably most professional drift S chassis cars run an underdrive pulley. I can tell you that SE-R Cup cars are very relaible with engines lasting several seasons sometimes. The one in my car has lasted about 2.5 seasons and is still going strong. My personal 529 whp turbo SE-R has an underdrive pulley. I don't know of an SR engine that has failed due to a pulley. I know several guys that have had them for 200,000 miles.

The same goes for the VG, VQ, QR and GA engines. Many World Challange race cars use underdrive pulleys.

Is an underve pulley harmless to all engines? No it is not. Inline six cylinders when modified way past the simple bolt on stages will probably have problems. These engines reach critcal harmonics at lower rpm due to the length of the crankshaft, this is in the 7500 rpm range, an rpm often reached by a performance engine. Now a BPU Supra or other mildly modded inline six will most likely be fine but one subjected to high rpm for long periods of time with lots of boost will probably suffer. In this case , the stock balancer is probably not adiquate either. In my experiance with I-6 Nissan RB engines the oil pump inner gear cracks first due to crank whip. For serious I-6 motors I use ATI or Fisher dampers. Crazy stroked out B series Honda motors with strokes approching 100 mm will also crack their oil pump gears and racing Nissan KA motors crack blocks. Thse motors need to have the revs limited, dry sumps and other special prep to deal with vibration in extreme full race use in very highly modifed form. American V8 engines are often externaly balanced and it is critcal not to use a solid hub pulley not designed for this applcation or damage to the engine will result.

Our tC engine and most people's here have motors that do not fall into the above catagory. Rest assured that your engine will not blow up and die or have a reduced life in street and even racing use with these parts. Will you notice more noise from the drivetrain and front end accesories, yes posibly.

I would bet that every "expert" that tells you otherwise here has little personal practical expericance with the subject.

TCpete

game over.. ^^^ awesome response to this subject sir... thank god finally we have some people here who think performance is cooler then how many led's and neons you have on your car!

tC9o9

for any one who doubts his info, thats Mike Kojima.. he has been building engine for longer than some of us have lived.

hPower

Thank you MotoIQ

For those who do not believe what he says, look at the RACE TEAM on the NST website. www.NonStopTuning.com and look for yourself at how many track-only cars are using pulleys. And look at the level of motorsports competitions.

tC9o9

yes sir, and like mike(motoiq) said, these track cars are pushed to the limits for about 30 minutes non stop..

people say 100 miles on a track is like a 1000 miles on the street if not more, so if nothing is happening to these cars then i think you will be fine.

3min3m2

i really try to avoid pi**ing contests, but gotta ask on this one


1. whats the date of that book(not dissing, jsut asking, cause the cover looks kind of old)
2. personally, i am not a mechanical engineer, automotive enginer...im going into computer engineering, but cars are my hobby. Having run a solid NST pulley for a while, and looking at the difference between the two(stock vx NST) i personally(being of no scientific proof) can see no benefit, aside from slight noise absorbtion, from the small rubber ring on the stock one....
3. is that book tC/CAmry/2AZ-FE specific??
4. would not the 4 cylinders, being in their specific firing order, and it being a 4-stroke engine, cancel out the vibrations every fourth RPM?? and for a v8 every 2nd?

i could see six cylinders having problems, and chevy's 5 cylinder engine even being worse...

but then again i am not an expert...

kungpaosamuraiii

Those are valid questions so I don't mind. I only hate blanket refusals based on the event of something not happening.

1. I don't know when the book was published but it's old. I'd say early 90's old. It's not my book.

2. Toyota documents that "rubber ring" as damping both NVH and torsional vibrations. NVH is, I think, mostly a comfort/discomfort thing but torsional vibrations took down more than its share of bridges. When the "symptoms" were brewing no one could feel it either. I don't think torsional vibrations are transmitted very well through the chassis but rather, releases its energy through bolts and chains and whatever is directly connected to the crank.

3. The book discusses Toyota technology and the damper technology hasn't changed. The rubber ring sandwiched between plates is probably the cheapest damping Toyota felt was necessary. That book states that it's used for both NVH and torsional vibrations. So as far as the pulley goes, torsional vibrations are relevant to the 2AZ.

4. I don't know too much about that. If that's true, that'd be great news.

Honestly, MotoIQ's post makes a lot of sense. I was referred to those pages by someone who's involved in Supras and of course, those run I6 engines with exceedingly long crankshafts. I think the best evidence for the tC's not detonating, thus far, is that it uses a very stout, short, and forged stock crank shaft.

I'm no expert either. But the tC is my only means of transportation so I would opt to become an expert in whatever I put on my car. I researched pullies a little and found torsional vibrations. MotoIQ presents some new information to me that explains away a lot of stuff. However, I would find out more about resonating metal.

And honestly, the gains really aren't worth running into torsional vibrations. If you take away danger from resonant frequencies then it's still not a very worthwhile mod, in my opinion. I'd rather get lightweight wheels. Not only would they save considerably more weight than a few ounces, they'd look good too.

MotoIQ

The stock damper helps atinuate torsional vibrations of a different order and magnitude that tend to make a rumbling or knocking noise at lower rpm. These are not the destructve vibrations at a higher rpm that have enough energy input to actualy cause posible harm.

The stock damper is not tuned to effectivly damp these out either.

When you go to a lighter flywheel and/or pulley it is not uncommon for these noises to become much louder. Some cars they can become very loud. On my 300zxtt with its twin disc super light. super low inertia solid hub clutch, the harmonic noise is extremely loud at 2500 rpm. If this was a daily driver it would be totaly unacceptable. When you put a light flywheel in a 350Z there is a noticable increse in engine vibrations.

For an all out race engine that dwells about the cranks second harmoinc in its powerband, it can be prudent to got to ATI, Fisher or Fluidamper and work with them on a damper that can help control these vibrations. Some of the signs of problems are broken oil pumps, sheared keyways, cracked cranks, sheared flywheel bolts, sheared pulley bolts, cracked blocks, strange bearing wear patterns.

These sorts of problems are more common in V-6 engines. I have seen them in the following i-4's, B series Honda motors with strokes at 100 mm or greater, Nissan KA24D, and Nissan QR25DE motors and thats about it. These motors were highly modied, spun really hard and were used in drag racing, class 7 truck racing and World Challange sccordingly. The QR25DE has a 100mm stroke and a pretty wimpy low overlap crankshaft.

All of these applications were high dollar, factory race team level racing unter extreme condtions.

I have never seen problems with solid hub pulleys on any street 4 cylinder no matter how hard it was driven and very few race applications other than the above mentioned ones.

So in short, don't worry, the vibrations that the pulley was designed to damp are a different order and lower rpm with less energy that can damage your engine. it might be more noisey though.