Cons to a lowered weight pulley set?

[Infamous Performance]

Originally Posted by industrial

Can you elaborate? Was this a fa20 or ejxxx? What else was done on the customers car? Have you really seen such a history of failure with this combination that you have established causation? I really hope this wasn't one customers wrx three years ago or some shit like that.

I have seen it happen many, many times over the years on EJ's. Most EJ builders will give you the same info if you ask. I rebuilt an EJ that was 2000 miles old (turbo blew and took out the fresh motor) just 2 months ago. I did not build the first motor, the car came in from out of state. It had a LWCP and a LWFW for the 2000 mile life of the motor. Crank bearings were SHOT when I cracked it open. Shot, like they had 200k with low oil on them. Same old song and dance. When I built the motor, it left with a stock crank pulley on it. and the LWFW. Customer chose the FW over the pulley. I have seen it so many times I never recommend both. If I see both, I note it on the invoice and inform the customer.

I have now rebuilt 2 FA20 motors (1 super charged and 1 turbo charged) that were using a LWCP and a LWFW. Both had bearing issues just like the EJ's do. I confirmed with another local builder and they too have seen the same issues. I build about 3 motors per month. They build about 40. We have the same experiences and we make the same recommendations.

[stugray]

Based on this:

Originally Posted by Infamous Performance

When I built the motor, it left with a stock crank pulley on it. and the LWFW. Customer chose the FW over the pulley. I have seen it so many times I never recommend both. If I see both, I note it on the invoice and inform the customer.

I have now rebuilt 2 FA20 motors (1 super charged and 1 turbo charged) that were using a LWCP and a LWFW. Both had bearing issues just like the EJ's do. I confirmed with another local builder and they too have seen the same issues. I build about 3 motors per month. They build about 40. We have the same experiences and we make the same recommendations.

Can you comment on my statement above:

Originally Posted by stugray

Interesting
.....
So based on those statements one can deduce that:

A LWFW coupled with a stock pulley will NOT prematurely damage your bearings.

WHY would that be?

[Infamous Performance]

I have not seen a LWFW destroy bearings on its own, unless... it was too light. On an EJ anything under 14lbs is pushing it. 12lbs is a no go. At 12lbs the FW is so light it causes misfires.

I have not tried to find the breaking point in an FA. It gets kind of expensive, lol. But I have not seen excessive wear on an FA from just a LWFW (yet, you never know).

I have also not used/installed a FA20 LWFW at less than 14lbs (yet).

[Boofneenee]

put your money towards something with greater return.

[DC2R]

Originally Posted by Infamous Performance

I have not seen a LWFW destroy bearings on its own, unless... it was too light. On an EJ anything under 14lbs is pushing it. 12lbs is a no go. At 12lbs the FW is so light it causes misfires.

I have not tried to find the breaking point in an FA. It gets kind of expensive, lol. But I have not seen excessive wear on an FA from just a LWFW (yet, you never know).

I have also not used/installed a FA20 LWFW at less than 14lbs (yet).

So no problem running light weight pulleys unless also running lwfw is what i take from this, yes?

Sent from my SM-N900T using Tapatalk

[stugray]

Originally Posted by Infamous Performance

I have not seen a LWFW destroy bearings on its own, unless... it was too light. On an EJ anything under 14lbs is pushing it. 12lbs is a no go. At 12lbs the FW is so light it causes misfires.

I have not tried to find the breaking point in an FA. It gets kind of expensive, lol. But I have not seen excessive wear on an FA from just a LWFW (yet, you never know).

I have also not used/installed a FA20 LWFW at less than 14lbs (yet).

So what you are saying is that by running the stock pulley with the Lightened Flywheel there is no problem with the engine damaging the bearings.

But with a light weight (billet) pulley and a lightened flywheel the bearings can be damaged.

I wonder what the stock pulley has that the lightened pulley does not.

[industrial]

I wonder how many people bother to have the clutch cover and flywheel balanced before installing. Flywheels are usually balanced well but as an assembly with the cover they can be off by a lot. They need to be balanced together. Perhaps changing the stock balanced rotating assembly with some unbalanced parts induces some need for the compliance inherent in the stock pulley. The stock pulley is a harmonic balancer which is not required by the engine according to oem engineers.

[tennisfreak]

There have been blown motors by owners with LWCP installed and had full warranty honored by the manufacturer (and no they did not remove it prior to taking it in).

There are document threads on this in the issues section.

If the LWCP was truly a big deal I dont see the manufacturer letting something like this go when having to rebuild an engine under warranty.

[Infamous Performance]

Originally Posted by DC2R

So no problem running light weight pulleys unless also running lwfw is what i take from this, yes?

Sent from my SM-N900T using Tapatalk

Correct. I have not seen issues from a LWCP alone.

[Infamous Performance]

Originally Posted by stugray

So what you are saying is that by running the stock pulley with the Lightened Flywheel there is no problem with the engine damaging the bearings.

But with a light weight (billet) pulley and a lightened flywheel the bearings can be damaged.

I wonder what the stock pulley has that the lightened pulley does not.

Yes to the first statement and question.

Mass and a small bit of vibration dampening to the second question.

[Infamous Performance]

Originally Posted by tennisfreak

There have been blown motors by owners with LWCP installed and had full warranty honored by the manufacturer (and no they did not remove it prior to taking it in).

There are document threads on this in the issues section.

If the LWCP was truly a big deal I dont see the manufacturer letting something like this go when having to rebuild an engine under warranty.

The Magnuson-Moss Warranty Act
http://www.sema.org/sema-enews/2011/...ermarket-parts

[stugray]

Originally Posted by Infamous Performance

Mass and a small bit of vibration dampening to the second question.

THANK YOU!

Finally someone (with credibility) said it!
The stock pulley provides vibration dampening that the Light weight crank pulleys do not!

AND has data to support that statement.

[Infamous Performance]

Yes. The stock OEM crank pulleys do absorb some vibration. They are technically 2 pieces separated by a thin rubber "absorber". When the pulleys age (heat also seems to play a role) the pulleys can eventually separate. I have seen this too (catastrophic loss of the engine). The separation "issue" is one of the factors that drove many early EJ adopters to the single piece LWCP.

[Poodles]

Originally Posted by industrial

I wonder how many people bother to have the clutch cover and flywheel balanced before installing. Flywheels are usually balanced well but as an assembly with the cover they can be off by a lot. They need to be balanced together. Perhaps changing the stock balanced rotating assembly with some unbalanced parts induces some need for the compliance inherent in the stock pulley. The stock pulley is a harmonic balancer which is not required by the engine according to oem engineers.

Clutch components are zero balanced, so they don't need to be balanced together unless they're sub-par.


There is still no proof that the OEM engineers said anything of the sorts...

Originally Posted by Infamous Performance

Yes. The stock OEM crank pulleys do absorb some vibration. They are technically 2 pieces separated by a thin rubber "absorber". When the pulleys age (heat also seems to play a role) the pulleys can eventually separate. I have seen this too (catastrophic loss of the engine). The separation "issue" is one of the factors that drove many early EJ adopters to the single piece LWCP.

Yep, it's common to run ATI dampers in the other car circles I run in because of this failure (as the OEM pulley is actually more expensive). Not to mention ATI is SFI rated while none of the normal LWCPs are.


Generally speaking though, pulleys are a bling item and nothing more (unless you're talking underdrive pulleys which introduces it's own set of issues).