Cause of blown motors?

[blackhawkdown]

New alternative to a Light Weight Pulley

[stugray]

For all of those naysayers:

The pulley in question: The Stock Pulley on the BRZ.

Is a textbook torsional dampener period.
Look it up in a dynamics textbook, or google images.

https://www.google.com/search?hl=en&...93.ZhHdB7ZrnCg

That is what it is. There is no debate.
Balancer, pulley, whatever.....

One of the things I do for a living is dynamic testing.
My office is on the third floor of one of the most advanced dynamics testing facilities in the country.
SO I can look at the pulley from our car, and a solid billet pulley and tell you just by touching and feeling the two different pulleys, for a fact, that the stock pulley has a much lower resonant frequency than the billet pulley.
I can also tell you (based on the manufacturing) that this was intentional by the engineers at Toyota.

WHY? - that is clearly up for debate

[industrial]

Originally Posted by stugray

For all of those naysayers:

The pulley in question: The Stock Pulley on the BRZ.

Is a textbook torsional dampener period.
Look it up in a dynamics textbook, or google images.

https://www.google.com/search?hl=en&...93.ZhHdB7ZrnCg

That is what it is. There is no debate.
Balancer, pulley, whatever.....

One of the things I do for a living is dynamic testing.
My office is on the third floor of one of the most advanced dynamics testing facilities in the country.
SO I can look at the pulley from our car, and a solid billet pulley and tell you just by touching and feeling the two different pulleys, for a fact, that the stock pulley has a much lower resonant frequency than the billet pulley.
I can also tell you (based on the manufacturing) that this was intentional by the engineers at Toyota.

WHY? - that is clearly up for debate

My guess as to why? NVH on foresters, legacys and out backs. It's out of a parts bin. Quit overthinking it. Damn engineers always thinking there is a complicated engineering reason behind everything and missing the obvious.

[stugray]

Originally Posted by industrial

Damn engineers always thinking there is a complicated engineering reason behind everything and missing the obvious.

So you are saying you are positive that there is not a sound engineering reason for this to be installed on the engine from the factory?
Sounds like "Engineering judgement" to me.

So again "On a car where the #1 goal of the engineering staff was to reduce weight, WHY did they put a ~7 pound item on when a 2 pound substitute would have sufficed?"

And the answer is NOT because a 3 piece machined steel assembly is cheaper than a machined billet aluminum disk. It is NOT cheaper.

[Apoc]

Originally Posted by stugray

For all of those naysayers:

The pulley in question: The Stock Pulley on the BRZ.

Is a textbook torsional dampener period.
Look it up in a dynamics textbook, or google images.

https://www.google.com/search?hl=en&...93.ZhHdB7ZrnCg

That is what it is. There is no debate.
Balancer, pulley, whatever.....

One of the things I do for a living is dynamic testing.
My office is on the third floor of one of the most advanced dynamics testing facilities in the country.
SO I can look at the pulley from our car, and a solid billet pulley and tell you just by touching and feeling the two different pulleys, for a fact, that the stock pulley has a much lower resonant frequency than the billet pulley.
I can also tell you (based on the manufacturing) that this was intentional by the engineers at Toyota.

WHY? - that is clearly up for debate

I don't think anyone is debating that it isn't a damper, obviously it's designed to be something more than just a crank pulley. Then question I have is if that thin bit of rubber is there to dampen the massive torsional forces that would otherwise destroy the engine or is it just to remove a bit of the NVH.

[s2d4]

Originally Posted by industrial

Damn engineers always thinking there is a complicated engineering reason behind everything and missing the obvious.

Damn people always thinking everything is so simple and there is no reason for the engineer to do that in the first place.
Guess what, it actually happens more this way than what you are referring to.

[suaveflooder]

Originally Posted by Apoc

I don't think anyone is debating that it isn't a damper, obviously it's designed to be something more than just a crank pulley. Then question I have is if that thin bit of rubber is there to dampen the massive torsional forces that would otherwise destroy the engine or is it just to remove a bit of the NVH.

my vote

[industrial]

Originally Posted by stugray

So you are saying you are positive that there is not a sound engineering reason for this to be installed on the engine from the factory?
Sounds like "Engineering judgement" to me.

So again "On a car where the #1 goal of the engineering staff was to reduce weight, WHY did they put a ~7 pound item on when a 2 pound substitute would have sufficed?"

And the answer is NOT because a 3 piece machined steel assembly is cheaper than a machined billet aluminum disk. It is NOT cheaper.

Read my last post. I believe two cast iron pieces molded together with rubber suited for use in any boxer engine will be significantly cheaper than a limited run of milled aluminum pulleys.

Why did they not use more composites to lighten the car?
Why did they ship the car with 20lb boat anchor wheels?
Why did they ship the car with such a terrible nav unit when $300 off the shelf units are better?
Why does the car come with a 40lb catback?

Get your head out of your ass. It's the bean counters more often than not. Engineers have to work around bean counters for everything on this budget car. How many documented failures have there been on EJ of FA motors due to a solid pulley? Any? Enough to cry this much about a hypothetical?

[blackhawkdown]

[TrqlessWonder]

Originally Posted by stugray

So you are saying you are positive that there is not a sound engineering reason for this to be installed on the engine from the factory?
Sounds like "Engineering judgement" to me.

So again "On a car where the #1 goal of the engineering staff was to reduce weight, WHY did they put a ~7 pound item on when a 2 pound substitute would have sufficed?"

And the answer is NOT because a 3 piece machined steel assembly is cheaper than a machined billet aluminum disk. It is NOT cheaper.

I've seen you make this assertion that CNC milling a pulley out of billet high grade aluminum is cheaper than what the factory gives you many times. You are mistaken.

One of the many ways I earn my living, is by manufacturing things. Making a nice, custom pulley is fairly straightforward. If I wanted to make a few copies of a bunch of different things, CNC is an excellent option. But, don't think that just because the nice one is machined from billet, that the factory unit is manufactured using similar processes/methods, just different materials.

Here, I'm trying to make a BUNCH of copies of just one or two things. The one coming from the factory wasn't milled out of a solid billet of anything. Too wasteful and not anywhere near fast enough for such a commoditized part. Here, it's not the CNCs going "hmmmmmmmmmSTRAAAAAAAAAAAAAINNNNNNNNNNNhmmmmmm mm" and then repaeat that several dozen more times to get one pulley out (that still needs assembling), it's the stamps and punches and presses that go "ka-thunk-a-thunk-a-thunk-a-thunk-thunk-a" that are producing six with every die strike, and then get whisked away to be automatically loaded into the automated assembly fixtures and welders. The most machining any of these parts see are just to clean up the face of the castings, and as you can tell from the surface finish, they can use some pretty crude tools to do that.

[stugray]

Originally Posted by industrial

I believe two cast iron pieces molded together with rubber suited for use in any boxer engine will be significantly cheaper than a limited run of milled aluminum pulleys.

And I believe the opposite. That a 1 piece machined Al. disk is cheaper than a three piece machined steel piece.

And WTF "LIMITED RUN"?!? How many of these cars are on the road now?

Your concept of "limited" is just as fucked up as who you think needs to get their head out of their ass....

The reason for all of you examples above is COST!
They chose to keep the cost down by putting on cheaper parts.
THAT IS WHY WE QUESTION the more expensive "pulley"

[stugray]

Originally Posted by TrqlessWonder

One of the many ways I earn my living, is by manufacturing things. .

I do as well. And It is cheaper to make a billett aluminum disk, than a three piece steel machined assembly. Period.

Anyone who thinks differently is smoking crack.

So you can honestly say that a factory will charge less to manufacture the stock pulley than a perrin pulley?

I can go downstairs in the building I am sitting in and make a perrin pulley in about 2 hours from scratch.
It would take me days to make a stock pulley.\


So with a straight face, you can honestly say that this costs more to manufacture:


Than this:


Both aftermarket parts....

In my business it would cost more just to have someone take the three parts out of a bag (parts kit) and assemble them than the CNC lathe running to make the al. part.

[suaveflooder]

Originally Posted by stugray

Than this:

Yeah, that looks exactly like the stock one.

[Basket Case]

Originally Posted by stugray

And I believe the opposite. That a 1 piece machined Al. disk is cheaper than a three piece machined steel piece.

And WTF "LIMITED RUN"?!? How many of these cars are on the road now?

Your concept of "limited" is just as fucked up as who you think needs to get their head out of their ass....

The reason for all of you examples above is COST!
They chose to keep the cost down by putting on cheaper parts.
THAT IS WHY WE QUESTION the more expensive "pulley"

I am not going to weigh in on which part is better, but for you to think that making a special part for one car when they can use the same/similiar part across their entire lineup doesn't change the cost of an item you would be wrong...