Welcome to the North American Subaru Impreza Owners Club Saturday March 28, 2015
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo)

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 01-10-2004, 09:24 AM   #1
Kitt
Scooby Specialist
 
Member#: 24621
Join Date: Sep 2002
Chapter/Region: Tri-State
Location: Long Island, NY
Vehicle:
2006 Legacy GT
2015 WRX STi

Default Perrin Crank Pulley problems

I read changing the stock crank pulley (EJ20) is a bad idea due to certain balancers. People using pulley's mentioned problems such as hesitation and misfires at high rpm. But, I came across a thread were someone contacted Subaru about the "job" of the crank pulley. Subaru replied that the crank pulley is nothing more than just pulley and there are no harmonic balancers. For those of you who had problems with aftermarket pulley's which brand were you using? Anybody have problems with the Perrin? I'm asking this because I have a Perrin pulley that I still need to install and was thinking this would be the best pulley because it's the same size as stock but lighter. Thanks.
* Registered users of the site do not see these ads.
Kitt is offline   Reply With Quote
Old 01-10-2004, 09:29 AM   #2
Johnzim63
Scooby Newbie
 
Member#: 33330
Join Date: Feb 2003
Location: western NY
Vehicle:
2002 WRX 5spd sedan
WRB

Default

I've had the TB Racing crank pulley on my car for over a year with no problems like that. Of course, I don't do a lot of hard driving or any racing. It is a lightened but full-size pulley. It's also a pretty anodyzed blue *bling bling*.
Johnzim63 is offline   Reply With Quote
Old 01-10-2004, 10:25 AM   #3
Uncle Scotty
Scooby Guru
 
Member#: 16200
Join Date: Mar 2002
Vehicle:
OK Houston
we have an Uncle

Default

I have had the Perrin on my car for ~20k miles with no problems.
Be absolutly sure that you understand the install instructions and the attach bolt must be torqued to 90ft-lbs.
Uncle Scotty is offline   Reply With Quote
Old 01-10-2004, 10:40 AM   #4
Unabomber
Big Ron
Moderator
 
Member#: 18062
Join Date: Apr 2002
Chapter/Region: MAIC
Location: I can save you a ton of cash
Vehicle:
on car parts so PM
me b4 j00 buy

Default

When I spoke to Cobb about pulley issues they said that the issues occur regardles of manufacturer, type, underdriven, or just lightened.

Pulley FAQ for more info.

Perrin's are not OEM size, it is just a smidge underdrive. By a smidge, we are talking a mm or two at most. I have a Perrin and have had no problems with it.
Unabomber is offline   Reply With Quote
Old 01-10-2004, 11:04 AM   #5
Kitt
Scooby Specialist
 
Member#: 24621
Join Date: Sep 2002
Chapter/Region: Tri-State
Location: Long Island, NY
Vehicle:
2006 Legacy GT
2015 WRX STi

Default

Thanks guys, anybody else?
Kitt is offline   Reply With Quote
Old 01-10-2004, 01:56 PM   #6
TB RACING
Vendor
 
Member#: 47651
Join Date: Nov 2003
Location: Queensbury, New York
Vehicle:
02 WRX
Blue

Default

We've yet to have a customer complaint on our pullies.
TB RACING is offline   Reply With Quote
Old 01-10-2004, 02:04 PM   #7
Saunders
Scooby Specialist
 
Member#: 34480
Join Date: Mar 2003
Chapter/Region: MAIC
Location: Glen Burnie, MD
Vehicle:
2003 WRX Wagon
Blue

Default

Another for the perrin crank pulley. Works great, notice it especially at lower speeds, in 1st/2nd gear. It is easy to install, assuming you have a torque wrench and maybe a breaker bar.

Saunders
Saunders is offline   Reply With Quote
Old 01-10-2004, 04:16 PM   #8
rossscarbro
Scooby Specialist
 
Member#: 34627
Join Date: Mar 2003
Location: Riverside county, Socal!!
Vehicle:
2006 Evo IX GSR
Graphite Grey

Default

The only problem I ever had with my pulley was the install!

It's hard for me to say if I've noticed a difference with it or not, but no probs now for close to 5,000 miles.
rossscarbro is offline   Reply With Quote
Old 01-10-2004, 06:30 PM   #9
pjcoregon
Scooby Specialist
 
Member#: 15384
Join Date: Feb 2002
Chapter/Region: NWIC
Location: Portland, Oregon
Default Re: Perrin Crank Pulley problems

Quote:
Originally posted by Kitt
I read changing the stock crank pulley (EJ20) is a bad idea due to certain balancers.
This is not true with the Subaru boxer engine... there are no balancers or dampeners.
pjcoregon is offline   Reply With Quote
Old 01-10-2004, 07:33 PM   #10
nhluhr
John Wayne Toilet Paper
Moderator
 
Member#: 7327
Join Date: Jun 2001
Chapter/Region: NWIC
Location: Seattle, WA
Vehicle:
2008 Mazdaspeed3
2006 Wrangler Sport

Default

Quote:
Originally posted by pjcoregon
This is not true with the Subaru boxer engine... there are no balancers or dampeners.
Yes, actually the stock crank pulley has a heavy chunk of rubber built into it. It is in fact a dampener.
nhluhr is offline   Reply With Quote
Old 01-10-2004, 09:15 PM   #11
AllSeven
Scooby Specialist
 
Member#: 32798
Join Date: Feb 2003
Location: CT, south side windsor
Default

i could care less about rubber just the balence that kinda scares me
AllSeven is offline   Reply With Quote
Old 01-11-2004, 12:42 AM   #12
Happy_Days
Scooby Specialist
 
Member#: 35049
Join Date: Apr 2003
Chapter/Region: VIC
Location: Vancouver BC
Vehicle:
2011 Mercedes C63
OE Tune 538/500

Default

I've been using the GFB pulley kit, works great. Included alternator pulley and crank pulley. It's lightened and smaller. No problems.
Happy_Days is offline   Reply With Quote
Old 01-11-2004, 01:06 AM   #13
cooter
Scooby Specialist
 
Member#: 23258
Join Date: Aug 2002
Location: Tennessee
Vehicle:
2005 STi
White

Default

I've had a Vishnu underdrive pulley on now for about 23,000 miles: as part of a stage 0, stage 1, and then stage 2 car. No problems to report.
cooter is offline   Reply With Quote
Old 01-11-2004, 09:34 AM   #14
wcbjr
Scooby Guru
 
Member#: 4001
Join Date: Feb 2001
Location: I love spherical bearings!
Vehicle:
2006 Legacy GT
Obsidian black

Default

Quote:
Originally posted by nhluhr
Yes, actually the stock crank pulley has a heavy chunk of rubber built into it. It is in fact a dampener.
Quote:
Thank you for your patience as I checked with our Technical Services Department regarding your message below. They advised that the crank pulley is a pulley and nothing else. It is not used as a harmonic damper/balancer.

Thanks for the opportunity to be of assistance. If you need any future assistance, please feel free to contact us again.

Best wishes,

John J. Mergen
Subaru of America, Inc.
wcbjr is offline   Reply With Quote
Old 01-11-2004, 10:23 AM   #15
Kitt
Scooby Specialist
 
Member#: 24621
Join Date: Sep 2002
Chapter/Region: Tri-State
Location: Long Island, NY
Vehicle:
2006 Legacy GT
2015 WRX STi

Default

Quote:
Originally posted by wcbjr
You don't believe in the SOA letter either? Or that was for nhluhr?
Kitt is offline   Reply With Quote
Old 01-11-2004, 04:29 PM   #16
mikkyo
Scooby Specialist
 
Member#: 25399
Join Date: Sep 2002
Location: Silly Valley, CA
Vehicle:
2003 Impreza WRX
Black

Default

I've had a Perrin crank pulley for 20K+ miles with no issues at any rpm.
I've never gotten a misfire CEL, and the car has been taken to redline, and driven in the upper RPM band, many times.

Just be sure you get it installed properly, mind the woodruff key, and torque it correctly.
mikkyo is offline   Reply With Quote
Old 01-11-2004, 04:53 PM   #17
pjcoregon
Scooby Specialist
 
Member#: 15384
Join Date: Feb 2002
Chapter/Region: NWIC
Location: Portland, Oregon
Default

Quote:
Originally posted by nhluhr
Yes, actually the stock crank pulley has a heavy chunk of rubber built into it. It is in fact a dampener.
Interesting... I'll have to go out and look at mine in the garage now... if there is a chunk of rubber built into it then its only purpose would be to dampen vibrations at certain frequencies and thus be a harmonic dampener.

I know I've never encountered a problem with a lighter crank pulley.

edit: my 02 pulley does indeed have rubber and does therefore have a harmonic dampener. thanks for correcting me.

Last edited by pjcoregon; 01-11-2004 at 10:12 PM.
pjcoregon is offline   Reply With Quote
Old 01-11-2004, 10:06 PM   #18
hippy
Scooby Specialist
 
Member#: 36528
Join Date: May 2003
Location: florida
Vehicle:
2002 Impreza Wrx
Silver

Default

Quote:
i could care less about rubber just the balence that kinda scares me
Quote:
Hello,
WRXfred: stock pulleys have some amount of rubber (or for some cars, especially american cars, the pulley is filled with fluid) on them to dampen engine vibrations. The exact design of the rubber, the amount, location, density, etc., is all designed to make the factory engine as reliable as possible so the OEM doesn't have to pay for repairs during the powertrain warranty.

"Harmonics" are "vibrations". Just replace the word "harmonics" with the more general word "vibrations" in my post and you'll get the meaning.

The orders of harmonics is... oiy. Is a whole class in physics. Uhh, another attempt by me to be brief: okay, the engine doesn't spin smoothly. About twice every rotation of the crank, there's an explosion that is transfered through the piston to the rod. The rod is offset from the center line of the crankshaft (ie, the journals stick out funny when you look at a crankshaft, so it looks like a funky bent piece of metal instead of one long rod), so the force that it exerts tries to twist the crankshaft.

The flywheel has the greatest rotational inertia of the system - ie, it's harder to stop a spinning flywheel with your hands than it is to stop a spinning rod, because the flywheel, with weight far from its center, "wants" to keep turning more. Since the flywheel has that rotational inertia, it keeps everything spinning at a constant speed. It makes the engine smoother.

Argh. I'm trying to explain this without getting too technical and it's not easy. Take a cardstock tube, like the tube in the middle of a roll of paper towels. Have someone hold one end. That friend is the flywheel. Have him rotate the tube slowly. Now, put your hand on the tube and suddenly try to speed it up as fast and hard as you can. What happens? You twist the tube and probably crush and ruin it, right? Your muscles are the explosion and your arm is the connecting rod and your hand is the beg-end of the rod. That's what's happening in the engine every time a cylinder has a combustion in it.

Fortunately, the heavy metal of the crankshaft is stronger than that tube. But it's not infinitely stiff. So there's a little bit of that going on all the time. The crankshaft speeds up a little bit under each of the cylinders. It twists a little bit. But as you know, you twist metal a little and it springs back. The flywheel side of the crankshaft moves at a constant speed, but this twisting action shows up at the far end of the crank (the side with the pulley). On a long engine, like an in-line 6 or a v-12, the vibrations can become HUGE. The twisting effect becomes huge. The flywheel turns steady, but all those various twists that are springing back get transmitted to the nose of the crankshaft.

While it's worse in longer engines, in shorter engines, it's still there. We happen to have the shortest engine - a 2-cylinder long crankshaft. So the vibrations aren't expected to be huge.

The OEMs design pulleys that take into consideration all of that springing back and forth that's happening as the crankshaft rotates. They spend literally hundreds of thousands of dollars analyzing everything they can, some on computer models, some on prototype engines, to determine EXACTLY how the crankshaft will spring around and what to do to soften that springing. That is the function of the pulley. The "harmonic" balancer or damper.

Oh, so what's a harmonic? Drop a pebble in a bath tub, along one of the walls. Watch the waves go outward, hit the other walls, come back to the starting point, bounce off that wall, etc. Now drop another pebble in the same spot. Now look carefully. You see the small waves riding on top of the bigger, faster waves that you just made? The small waves, which are on their second trip, are second order waves. When they bounce back again, they'll be third order waves. Watch them VERY carefully. Sometimes, they'll dissappear into the bigger wave and for a short instant, you get a slightly bigger wave. The waves are constructively interfering with each other.

Now translate that to the crankshaft. Its twisting / springing as it turns. It's kinda going boing-boing-boing-boing as it spins. If you were standing on the crankshaft nose (and you were really tiny and had really sensitive equipment), you would notice that your speed is actually 5000 rpms plus a few thousand times a second, you're a little faster than that and a few thousand times a second, you're a little slower then that. You're boinging back and forth from the harmonics. Except they're piling on top of eachother. And sometimes, the waves/twisting combines together and you get a really big wave / twist. That's a spike in the harmonics. That's really dangerous. Your crankshaft can bump enough to cause damage to the bearings or can actually twist itself and damage itself.

BTW, on some in-line 6 engines, an aftermarket pulley is so detrimental that if you watch the pulley under a really high speed strobe light, you can see variations in the pulley position. This is called a really bad thing!

Joel

peace
hippy is offline   Reply With Quote
Old 01-11-2004, 10:21 PM   #19
pjcoregon
Scooby Specialist
 
Member#: 15384
Join Date: Feb 2002
Chapter/Region: NWIC
Location: Portland, Oregon
Default

Quote:
Originally posted by AllSeven
i could care less about rubber just the balence that kinda scares me
I'm assuming that you missed Nikola Tesla and harmonic resonance while in school... the short version is that all materials have a natural frequency at which they will resonate/vibrate. Inreasing the generation of that sound/vibration will cause them to vibrate to the point of disentegration.
pjcoregon is offline   Reply With Quote
Old 01-11-2004, 10:22 PM   #20
nhluhr
John Wayne Toilet Paper
Moderator
 
Member#: 7327
Join Date: Jun 2001
Chapter/Region: NWIC
Location: Seattle, WA
Vehicle:
2008 Mazdaspeed3
2006 Wrangler Sport

Default

Quote:
Originally posted by pjcoregon
I know I've never encountered a problem with a lighter crank pulley.
I also have never had problems. There's been a Vishnu lightweight underdrive pulley on my car since 40,000 miles ago.
nhluhr is offline   Reply With Quote
Old 01-11-2004, 10:42 PM   #21
hotrod
Scooby Specialist
 
Member#: 14141
Join Date: Jan 2002
Location: 13.239@102.85 @ 5800 ft on 13T
Vehicle:
2002 Impreza WRX

Default YMMV

This is one of those YMMV issues. There are a large number of folks who have had them on their cars for quite a while with no problems that they can trace to the pulleys. There are also a handful of folks that have seen very solid repeatable evidence of problems with "their engines". If you do a search on damper, or dampener or harmonic you will see this topic gets beat to death every few months, and about a year ago there were some very long threads on the topic.

I choose not to use one because there is a large body of evidence that it is bad practice to run a internal combustion engine without one.

Engineers have bumped into this repeatedly for the last 60 -70 years. Some very weird problems have been traced to lack of proper dampening, some of them are not the sort of thing the average person would even consider as being connected to a damper. Issues like broken distributor drives and oil pump drives, wild spark timing scatter etc. Each engine is different and to some extent it depends on how you drive and tune your car as well.

The short crank shaft of the subaru engine is more resistant to some of the torsional harmonic issues that are well documented on longer engines like the BMW 6 cylinders which break crank shafts if you take the damper off and drive them hard. That does not mean there is no damage to the subaru, just that it is not as obvious as a broken crank, and may not show up for years.

If you want one buy it and try it if any wierd things start happening , take it off and see if it makes a difference.

Larry
hotrod is offline   Reply With Quote
Old 01-12-2004, 09:38 AM   #22
Rich10
Scooby Specialist
 
Member#: 14934
Join Date: Feb 2002
Chapter/Region: Tri-State
Location: Long Island
Vehicle:
2002 WRX
WRB

Default

Quote:
Originally posted by pjcoregon
I'm assuming that you missed Nikola Tesla and harmonic resonance while in school... the short version is that all materials have a natural frequency at which they will resonate/vibrate. Inreasing the generation of that sound/vibration will cause them to vibrate to the point of disentegration.
Its just strange that I have yet to hear of any part on a Subaru flat four engine disintegrating because of an aftermarket pulley.

BTW, I have had the GFB pulleys for a year and a half with no CEL's or knock indications from my utec.
Rich10 is offline   Reply With Quote
Old 01-12-2004, 10:14 AM   #23
wcbjr
Scooby Guru
 
Member#: 4001
Join Date: Feb 2001
Location: I love spherical bearings!
Vehicle:
2006 Legacy GT
Obsidian black

Default

60000 miles on my old RS(T) without incident
wcbjr is offline   Reply With Quote
Old 01-12-2004, 12:16 PM   #24
hippy
Scooby Specialist
 
Member#: 36528
Join Date: May 2003
Location: florida
Vehicle:
2002 Impreza Wrx
Silver

Default

Quote:
Its just strange that I have yet to hear of any part on a Subaru flat four engine disintegrating because of an aftermarket pulley.
There are many people out there that have had different problems with their engines while having aftermarket crank pulleys on them. Maybe some of those people will speak up(I e-mailed a few people, just so they can chime in ). The problem is that it's not so easy to relate the problem to the crank pulley. I also know of many people who were seeing knocks under 3000rpm while decelerating with a aftermarket crank pulley. Some people call this a "false knock", but I don't really beleive in such things.

If ya do a search of "engine damage" or "false knock" and check how many people have an aftermarket crank pulley out of those people, you might draw some conclusions. Anyways, it's obvious how I feel about aftermarket crank pulleys, but I'm no expert. I'm not someone who's trying to sell anything, and I was just puting that info out there so people who thought there were only benifits to aftermarket crank pulleys knew both sides of the coin.

peace
hippy is offline   Reply With Quote
Old 01-12-2004, 01:07 PM   #25
pjcoregon
Scooby Specialist
 
Member#: 15384
Join Date: Feb 2002
Chapter/Region: NWIC
Location: Portland, Oregon
Default

Quote:
Originally posted by Rich10
Its just strange that I have yet to hear of any part on a Subaru flat four engine disintegrating because of an aftermarket pulley.

BTW, I have had the GFB pulleys for a year and a half with no CEL's or knock indications from my utec.

I've had one for 45k... but it is worth noting that it is not without risk. And what tesla postulates requires you to hit the correct frequency for the material and the frequency applied with force for an appropriate amount of time.
pjcoregon is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Perrin crank pulley vs. GFB 2 pcs pulleys gopsu Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 6 10-21-2008 06:37 PM
FS: Socal: Perrin crank pulley, Perrin Fuel Rail Kit, Injen Cross-Pipe. RSXiMUS Engine/Power/Exhaust 7 04-30-2008 05:54 PM
I will trade my perrin crank pulley for a stock crank pulley NITROS Mid West Subaru Owners Club Forum -- MWSOC 8 07-21-2006 10:51 AM
Perrin Crank Pulley Vs Unorthodox Racing Ultra S lightened underdrive crank pulley west_minist Normally Aspirated Powertrain 3 02-21-2005 11:56 PM
Perrin crank pulley problem WRXVII Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 5 12-03-2002 12:02 AM


All times are GMT -4. The time now is 12:22 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2015 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.