Cause of blown motors?

[stugray]

Originally Posted by Basket Case

when they can use the same/similiar part across their entire lineup doesn't change the cost of an item you would be wrong...

Why do they use the more expensive part at all?

Why dont they use the cheaper billet al. pulley on all models?

[Poodles]

Originally Posted by industrial

You do realize that subaru has been using almost the same part on all their cars for years right? That one below is from my 2002 Forester. This isn't some custom engineered part just for the BRZ. Sometimes car markers do things for people called "bean-counters". I'm not sure I understand that this part is more expensive than a machined aluminum part. You aren't thinking about economics of scale. It maybe cheaper to buy 100 machined aluminum pulleys. It's definitely cheaper to buy 100,000 cast iron pulleys which can be used on a wide variety of vehicles, many of whom may have NVH issues with a solid pulley.

Oh for the love of god, that looks similar to the one on this car, yes. Just like all shocks for cars look similar but are not the same. Mass production costs are for the same item, not similar but different items, so your point is invalid.

Originally Posted by stugray

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.

The Perrin pulley is made to look cool with it's cutouts, and could be made far cheaper and with less machining operations. That alone is proof of the typical marketing for bling...

Originally Posted by suaveflooder

Yeah, that looks exactly like the stock one.

Both are elastomer dampers, one is just made to a higher standard and won't come apart in the even of the elastomer failing (which is why it's SFI rated).

Originally Posted by Basket Case

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...

Yet again, it's NOT the same part. Similar = different = more cost for OEMs so you're making my case for me.

Originally Posted by stugray

Why do they use the more expensive part at all?

Why dont they use the cheaper billet al. pulley on all models?

Occam's Razor is a bitch to the naysayers isn't it? The obvious reason is that it's a properly engineered part and necessary for the longevity of the engine.

[charged86]

this thread is insane. I just talked to ATI and they really wouldnt admit that the car was internally balance. But he did say that nascar, and top fuel dragster engine builders ALL USE ATI. I said agian, the rumor is that my engine is internally balance. He said would you trust your built motor to a stock cast machined part or a part engineered to keep everything in check. I did just build a motor and it was very expensive. So i am considering this part as another insurance policy to protect my engine.

On a second note I am considering a larger pulley to gain more boost instead of going to an even smaller supercharger pulley. My custom one will probably be built out of aluminum and I dont care if its lighter or not I am more concerned about having everything in balance. ATI offered to make me a larger balanced pulley but it would be 6-9months out which is not something i would consider.

I know this really didnt help either argument here but from a owner's stand point who is going on a fairly large build.

[FirestormFRS]

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.

Economies of scale you dolt. The engine is used across many vehicles. The 86 was at the bottom of the rung when the engine was designed. Much more important to have a smooth and quiet Legacy than to eek better throttle response out of an 86.

[FirestormFRS]

Originally Posted by stugray

Why do they use the more expensive part at all?

Why dont they use the cheaper billet al. pulley on all models?

Oh you silly goose! You have no idea how much enough CNC machines to meet demand would cost. You have no idea how much tooling and maintaining said CNC machines cost. CNC is great and I love the ones I work with, but they are very expensive in comparison to casting iron. All steel/iron/aluminum parts would be CNC'd instead of cast if it were cheaper.

[TrqlessWonder]

Originally Posted by stugray

Why do they use the more expensive part at all?

Why dont they use the cheaper billet al. pulley on all models?

Because the billet part isn't cheaper. Stop thinking that the factory that produces the steel parts is using CNC mills to make each pulley. They are not. If I was a specialty shop that also did heads and valve covers and blah blah blah, and only needed to make a couple dozen of anything, sure, I'd stick you with a CNC mill for its flexibility. When I have to make enough for say, all subaru boxers, I ditch the flexible stuff and build a line whose sole job is turning out those pulleys.

You say it'll take you two hours to make a nice one from scratch. That may seem quick to you. But, it's nothing compared to the higher speed stuff in auto manufacturing. Those pulleys are getting churned out many orders of magnitude faster, using simpler materials and processes. Not a one-time run of 100, over the course of two months. More like (because they are supplying the auto industry, and these are the volumes for tier 1's) a couple of thousand, every day. What's cheaper, one guy watching lights on three automated machines that are running at a 100 pcs/hour rate, or one guy, on one mill, making a half-dozen a day?

All you really need to do is think of all the crazy things you'd have to do to make it possible to crank one out in 20 seconds' worth of machine cycle time, and then realize that a good manufacturer has already done the work necessary to make that rate happen.

[TrqlessWonder]

Originally Posted by stugray

Why do they use the more expensive part at all?

Why dont they use the cheaper billet al. pulley on all models?

Because the billet part isn't cheaper. Stop thinking that the factory that produces the steel parts is using CNC mills to make each pulley. They are not. If I was a specialty shop that also did heads and valve covers and blah blah blah, and only needed to make a couple dozen of anything, sure, I'd stick you with a CNC mill for its flexibility. When I have to make enough for say, all subaru boxers, I ditch the flexible stuff and build a line whose sole job is turning out those pulleys.

You say it'll take you two hours to make a nice one from scratch. That may seem quick to you. But, it's nothing compared to the higher speed stuff in auto manufacturing. Those pulleys are getting churned out many orders of magnitude faster, using simpler materials and processes. Not a one-time run of 100, over the course of two months. More like (because they are supplying the auto industry, and these are the volumes for tier 1's) a couple of thousand, every day. What's cheaper, one guy watching lights on three automated machines that are running at a 100 pcs/hour rate, or one guy, on one mill, making a half-dozen a day?

All you really need to do is think of all the crazy things you'd have to do to make it possible to crank one out in 20 seconds' worth of machine cycle time, and then realize that a good manufacturer has already done the work necessary to make that rate happen.

[suaveflooder]

Originally Posted by Monogram

There is currently a thread on this site where an owner lost an engine due to bearing failure. The only mod was a light crank pulley.

link please

[OrbitalEllipses]

Originally Posted by Monogram

There is currently a thread on this site where an owner lost an engine due to bearing failure. The only mod was a light crank pulley.

That does not indicate a causal relationship. Correlational, at best.

[suaveflooder]

Originally Posted by OrbitalEllipses

That does not indicate a causal relationship. Correlational, at best.

I honestly would just like to see the link. I've heard about this happening, but never actually seen it. It's always a brother of a friends who's sister metnioned it to him about her dad's car failing because of a lightweight pulley on a subaru.

I'm not saying it didn't happen, I've just never seen it with pics and evidence.

[OrbitalEllipses]

Originally Posted by suaveflooder

I honestly would just like to see the link. I've heard about this happening, but never actually seen it. It's always a brother of a friends who's sister metnioned it to him about her dad's car failing because of a lightweight pulley on a subaru.

I'm not saying it didn't happen, I've just never seen it with pics and evidence.

There's no way to prove the pulley was at fault, is all I'm saying.

Boxer engines are dynamically balanced by the motion of the pistons...but you won't see me with an aftermarket crank pulley.

[suaveflooder]

Originally Posted by OrbitalEllipses

There's no way to prove the pulley was at fault, is all I'm saying.

Boxer engines are dynamically balanced by the motion of the pistons...but you won't see me with an aftermarket crank pulley.

agreed 100%….I would still like to see what he has

[stugray]

Originally Posted by suaveflooder

It's always a brother of a friends who's sister metnioned it to him about her dad's car failing because of a lightweight pulley on a subaru..

Like the person who received the email from subaru which said that the pulley is not there for balance.....

[suaveflooder]

Originally Posted by stugray

Like the person who received the email from subaru which said that the pulley is not there for balance.....

"google" is your friend. There are plenty of thread about it. Might involve you to make more than an "assumption" though