OK, time for lights out.

Pa-pa and Ma-ma are on a new schedule starting tomorrow. Daughter started a new job and has a longer commute. Granddaughters will be arriving at 0715.

Nite all ........... ZZZZZZZZZZ

I am not disputing that article. I do not have the expertise to do so but.....
I am wary all the same. They (Fluidampr) are trying to sell their product. I look at their graph and say to myself "Holy shit! Just look at the difference their damper makes!" That is the intention. I am not suggesting what they are saying is incorrect but..
So what if the "vibration angle" goes from .225 to .05? Let me state I DO NOT KNOW ok? But sure it looks good in their sale pitch but why is it significant? Crankshafts oscillate and providing there is no nasty resonance I don't understand the issue.

I've read another part of their article:
"Crankshaft driven timing components and oil pump drives can be more susceptible to these high frequency vibrations."
My bold. That looks like marketing speak to me. They don't say "it does" they say "can be". As in might be, possibly, maybe.

Two other points:
1/ There has been no controlled testing of the effect of fitting a solid cp on the FA20 as far as I know and it would not be economically viable to do so.
2/ There doesn't seem to be a high correlation of engine failure with having fitted a lwcp.

Captain Snooze: regarding (2) i recall seeing posts from few shop workers about crank bearings having short live for EJ & FA engines they had rebuilt or repair for cases where both lightweight CP & FW were installed. Rather soon at it. Something along the lines that only one of them should be installed, not both.

Fluidamper also claims 2lbs of rotating mass does not behave as rotating mass...

I know nothing of harmonics in an engine, but I see only that harmonics exist on all 3 pulleys, with similar magnitude, but in different orders and rpm. And the OEM pulley seems worst of the bunch on that 2nd order line... But what's actually destructive? No idea. I tried researching but haven't found any materials...

It could be NVH is the only reason for a damper pulley.

Of course, the OP's wobbly install would definitely be bad.

C

My ej has lightweight crank pulley and flywheel, I always thought those were just rumors. Been 20k miles so far at around 300 whp, on an engine with 80k since rebuild

One of those posts of different experiences. Another. Later cites info from other shop doing even more rebuilds and with "similar experiences". It's my only car, and one i like & want to use for long time .. preferring to play on safe side.

Hey @why? ...... where did you run off to ...... ??

I wasn't done with you yet.

:D


humfrz

Now we're cooking with gas. I referred to the cost of the damper versus a solid CP because it was the most general argument I could think of to support my position.

1. The OEM commits considerable resources into understanding how each component responds to the environment in which it operates. The customer is not privy to the mounds of information collected but it exists.

2. I agree with you on this point but that does not mean I think it's a good idea.

Yeah, I recall those/that post. It was a respected builder (MAP? Element? I can't be bothered searching ) but the issue was the combination of the two when the flywheel was reduced below a certain mass. That is, one could have a lwcp and a lighter flywheel. One could not have a lwcp and light weight flywheel. There seemed to be a critical mass at which the engine fell apart when the flywheel mass was reduced too much.

Speaking of which.
There seems to be a lot of discussion about the pros/cons of a light weight crank shaft pulley but I don't seem to read much about the impact of a light weight flywheel on the harmonics of a crankshaft. I am hypothesising given the much greater mass of the flywheel it would play a greater role in crankshaft damping/harmonics.
I am totally out of my depth here.

As someone considering getting a lighter flywheel at a later date, I too would like to know how a lighter flywheel affects damping on stock cp.

I hear the mass of a flywheel allows it to absorb some vibration.

Sent from my Pixel XL using Tapatalk

Note that they were talking about turbo's. FA20dit and EJ turbos. Also note there are so many issues with ej's and the fa20dit's seem to also be having all sorts of problems. I see no reason to mess with the crank pulley on a turbo. More complexity changes things, however that article I posted trying to sell that so called damper proves everything has vibrations, and even the fancy expensive aftermarket damper sold as smoothing everything out actually just changes the vibrations and has more vibrations than the stock ones.

I went to sleep, it was way past my bedtime. I only responded because I was drunk. I really truly don't care what people think about this stuff, it has been hashed, rehashed ad naseum and people are trying to shove info about old school big block engines into tiny 4 cylinders and try and make everyone believe it is the exact same thing when it simply isn't.

Did you look at the entire article? Oh wait, no no you didn't. There are a bunch of graphs that show a bunch of different vibrations and the fluidampr supposedly specially made dampr has more vibrations in a bunch of different places over the stock one. They cherry pick above 5500 rpms on that graph you posted. Funny thing though most people dding there car are never ever going to get anywhere near there. Hell I shift at 2500 rpms or less. Also note even they admit it might add only 3 times more stress at most. Not exactly exploding engine type of levels there. Funny how nowhere in that article did they every say they actually stressed anything until it broke. Gee, I wonder why? Could it be that all three do the job just fine and there is no actual case where any of them could cause a condition that would actually cause damage? That is my educated guess.

don't need to be an expert to see no one will ever change their opinions. Also don't need to be an expert to see big block old school v8's are not tiny boxer engines. People can take the time to do their own research, all the info is on the web. Subaru's internally balanced engines mean it really doesn't matter.

No, that's silly. Almost as balanced though.

I've learned to hate pretty much all of humanity.
But you've struck a good point, there are engines that are way out of balance and need all sorts of things to make it not blow up. Some people decided that since some engines need this that must mean all of them do, which is of course nonsense.

There can be no clear failure of pulley's as it is not something people would do and never modify anything else. People do claim they have seen ej's and fa20dit's with failures in cars that happen to have lightweight pulley's among a bunch of other mods as well. Of course the problem is we are seeing failures in both engines in completely stock cars as well.

That's silly. It could be done because "it is how it has been done for decades and there is no reason to rethink it." Like the reason for how so much is done. The research put into thinking a new way to do it would probably cost far more than any benefit that could be seen. It could also be used in many different engines and vehicles as it is now, instead of making a unique design for every engine which would add unneeded cost and complexity. If it works right and doesn't fail, why should they try and change it? There are a ton of reasons for a company to use a part that has never failed and always worked instead of trying for something new and different in this one area. Also note aftermarket pulleys are really expensive, that fluidampr thing is $370. This really is not an area of a car where revolutionizing things would bring much press or praise, while screwing things up would really ruin reputations. I have no problem with Subaru being conservative, hell I am sure a lot of people wish they would be more conservative when it comes to ej25 engines. But to say every little piece and part is why it is because of some mythical reason that has nothing to do with cost savings or part sharing is silly.

nothing is necessary. We know they went the cheap route when it came to engine oiling, which is why the engine just can't rev much past 8300 rpm's without major modifications for the oil system. Hell we know they settled for the crickets, I assume fixing them would cost an absurd amount of money. The manual gearbox is one hell of a compromise, and it seems they compromised quality and usefulness for making it less expensive. I wish they had found other areas to cut costs like the interior, the wheels and tires, etc. I don't know why they made the wheelbase or the car as long as they did, would have been nice to make both shorter and lighter, but that doesn't mean they designed it that way, it probably means they borrowed parts from other vehicles to keep the costs down. I could go on, in general the car is the way it is because that was the least expensive way for them to do it, with few exceptions, and they still missed their original stated price goals by a ton.

I hate when people say the stock way is the best way, instead of the way they compromised for everything because they have so many other goals and qualifications other than making the car as sporty and fun to drive as possible. While the aftermarket has that one goal and can easily cost a heck of a lot more than the stock part it replaces without issue.

" More complexity changes things, however that article I posted trying to sell that so called damper proves everything has vibrations, and even the fancy expensive aftermarket damper sold as smoothing everything out actually just changes the vibrations and has more vibrations than the stock ones. "

Man, are you reading the same article? Because it actually says the opposite. Or is it again based on your extensive experience? Alternative facts?

Look I get it, it might be a marketing spin, but considering Fluidampr has been around for years, had stellar results on trucks and cars, and been tested independently by quite a few places, i tend to believe them instead of your personal uneducated opinion. No disrespect, just a choice. ;)

Here is another one that might interest you.
http://www.motoiq.com/MagazineArticl...dent-Test.aspx

Here is an educated answer from an engineer:
The crankshaft damper has nothing to do with engine balance and vibrations. Motion and oscillation of the powertrain, as an assembly, is addressed by your engine mounts, transmission mounts, and potentially roll restrictors.

The purpose of a crankshaft damper is to reduce the angular twist / deflection of the crankshaft. Combustion creates pressure. Pressure becomes load into the connecting rod which creates torque on the crankshaft. That torque creates deflection of the shaft as it's not infinitely stiff. Depending on the material, journal offset, length of the shaft, and loads created in the cylinders you can see several degrees of angular deflection in the crankshaft. I've seen an OEM crankshaft which displayed 7° of deflection without a damper. With the damper it was under 2°.

The mass of the crank damper and the stiffness of the spring element (the rubber part) are vital to the effectiveness of the damper. They control the resonant frequency of the damper and impact the effective damping. If you change the mass or change the spring stiffness you change the frequency at which it operates. If you don't have enough mass, even at the correct frequency, you don't provide sufficient damping. An incorrectly tuned damper could actually make things worse."

According to their graph at certain rpm there is more twist with the Fluidampr than with oem. I have no idea if any of this is significant.

Attachment 149553

This is a generalised explanation that may or may not have ramifications for the FA20 engine. Does the the FA20 crank twist 7 degrees with a lwcp? No, it does not. I am suggesting that broad sweeping statements cannot be attributed to every particular example. The most twist I could see with a lwcp from that Fluidampr article was 0.37 of a degree. I have no idea if this is significant.

DANG ...... this ol boy may be confused .......:confused0068:

@why? ....... are there two of you with the same forum name of "why?" .. ??

Back a couple months ago a "why?" started a thread entitled "Help with essential basics".

I quote:

"Help with essential basics
________________________________________
So I don't see any threads with this type of stuff, probably because it is obvious to most. But I've never really done my own maintenance on my car and have no real idea of where to start.

Basically I want to be able to change my own oil, rotate my tires, etc, start with the simple stuff, but I need the tools. I have a set of basic tools, aka wrenches, hammer, measuring tape.

I have a dirt with some gravel driveway, so I don't trust the jack that came with the car, and I know there are all sorts of different ways to raise the car for both oil changes and changing tires, what are the easiest and least expensive tools for someone getting started?

What other basic type of stuff do I need to buy that a beginner wouldn't even think of?

I obviously need a good jack, stands or something to keep the car off the ground, a good torque wrench for the wheels,etc. I've seen special wrenches for oil filters, but is that really necessary?

What type of containers do people use to drain the oil into, where do I get them, and what do I do with the used oil?

What else would be handy and what other basic maintenance would a beginner be able to do without too much hassle? I know I have the ability to do this type of stuff, I just don't have any clue about how or where to begin and I am looking for help".

----------------------------------------------------------------

Now, starting yesterday, a forum member named "why?" started posting in this thread like he/she was some kind of automotive engineering expert.

Are you one in the same "why?" .... ??

If so, how did you get so automotive smart and experienced in a little over two months?

:popcorn:


humfrz

True, however the peaks and troughs are not as accentuated with Fluidampr as they are with Stock. Mind you, the small variations in graph are very minimal. Once you go FI or high RPM for longer period is where those differences will put a lot of stress on the crank bearings , etc. At least that is what they say. Moto IQ has done a similar test I think.
These tests are ordered by the manufacturer and obviously they will be biased, unless the product is utter shite! On the other hand, I would somewhat trust some professional tests rather than some guy on the forum. Generally speaking that is.

Lol, that doesn't bode well for your input! :)

Please take that with my intended humor. I just found the self defeating comment funny.

LOL, I am not "that guy"! But i have to admit though, I have learned a lot from different people on forums that i know they have the experience and/or knowledge to back up their statements. Some of which I have the utmost respect!
You on the other hand...dont know man! You just post pics of borderline work appropriate pics, and that is about it. :) JK man!

:cheers:

What you are basically saying is you cannot actually refute anything I say, so you are going to attack me personally. I get it, it makes you feel big to attack other people with no basis. I can take it, still don't care. I've had a lightweight pulley set on my Yaris for 60,000 miles. It also has a lightweight flywheel, racing clutch, the lightest wheels on the market(6 lbs each) and over 106k miles.

You can also go check other actual forum members who run lightweight everything on these cars, but I guess you don't give a crap about real world knowledge, do you? You just want to make baseless personal attacks. Go for it.

huge difference between book smart and practical being able to do anything. Same reason those ASE certifications can be dubious, they are all book testing with no actual practical testing. You can become an ASE certified anything just by studying and memorizing without any actual experience in the field.

I can give you theory, research and boatloads of actual knowledge. I've never claimed to be a mechanic nor will I claim to be able to do much wrenching myself. I just don't have the room or the place to do my own maintenance, that is what happens when one lives in a 750 sq foot apartment in the middle of nowheresville. I've got a dirt and rock driveway and everyone says that is a bad deal for lifts.

I can also read marketing bullshit and see when graphs literally say the opposite of what an article says.

But sure attack me because you don't like what I say. Still no proof any pulley alone has ever caused any damage anywhere on our cars, and I highly doubt you will ever find it. Still zero proof that anything on our car is a harmonic anything. Nor is one needed.

Still just looking at 1 graph. There are a lot of graphs and they contradict everything the article states. They also do not prove anywhere any pulley has ever caused any damage to our cars. If they actually did real research and proved a pulley can cause damage, they might have something. But they never went that far.

And look, I have never said anything against that fluidampr damper. No idea why you think I have. I have just said their graphs show their damper causes more vibrations than stock in certain areas, which is 100% true. They also do not define anywhere if any vibrations their graphs show will ever or have ever caused anyone any actual damage in any actual cars. So those graphs might look pretty but they prove nothing.

That other article states the same thing. Three pulleys that all make a hp and torque figure that are easily within the error correction of every dyno ever created. Could they actually be legit? Sure maybe. But the difference is so tiny as not to matter. Then they give their opinions that everything is smoother with the fluidampr. Which again might be true, but could also just be bias knowing it is suppose to be smoother. Who knows.

This post is intense, so... to keep it going: @why? Where the fuck did you find 6lbs wheels? How big (or rather small) must they be to be that light? Unless of course, you were talking out of your ass, which seems to happens a lot on this thread :P

Yeah I'm not even gonna bother cleaning this mess up.