Welcome to the North American Subaru Impreza Owners Club Saturday March 28, 2015
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
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 > Normally Aspirated with bolt-on Forced Induction Powertrain

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.
Thread Tools Display Modes
Old 08-01-2001, 11:46 PM   #1
Scooby Specialist
Member#: 2213
Join Date: Aug 2000
Chapter/Region: NESIC
Location: Raymond, NH USA
1995 Impreza w/EJ255
Brilliant Red

Default Flywheels and Turbos?

Tonight my clutch showed that it is tired or transfering all the extra power of the turbo. It last well at 6psi for a stock cluth though. Anyway my question is what are people's thoughts about the value of a lightened flywheel? Is it worth it? I don't plan on going past 8psi if that matters. Also this car is my daily driver. Any input would be apprecited.
Subaru Salesman
* Registered users of the site do not see these ads.
yebokmj is offline   Reply With Quote
Old 08-01-2001, 11:58 PM   #2
Frank Army
Member#: 1457
Join Date: May 2000
Chapter/Region: SWIC
Location: Phoenix, AZ
1999 Outback Sport
Steel Blue Mica


I was thinking about doing a clutch and flywheel change on mine but decided against the flywheel. No real good reason other than need and money....

I no it's no help.... but it is an example....
kastle is offline   Reply With Quote
Old 08-02-2001, 12:04 AM   #3
Member#: 67
Join Date: Jul 1999
Chapter/Region: SCIC
Location: San Diego, CA
1999 Outlasting
the competition.


there are two ways of looking at it
if you have any thoughts about doing it then now is the time..
ahhh i put mine in when the tranny was out
tom@kartboy is offline   Reply With Quote
Old 08-02-2001, 12:16 AM   #4
Scooby Newbie
Member#: 1655
Join Date: Jun 2000
Location: Novato, CA
MY98 RS w/WRX Conv
I-Speed Tech

Thumbs up


I have pretty much the same setup, MY98 RS-T.

I put in a lightened flywheel, ACT PP & Stock Clutch when I had New head gaskets replaced under warranty. I did this when I was still NA.

I've always thought it was a GOOD mod, especially if you're replacing the clutch. Stock weighs 25lbs., mine is 14.9lbs. from Primitive. There are lighter ones that are chromoly that weigh in about 12lbs. As for mine, I don't have any drivability problems.

mcgyver is offline   Reply With Quote
Old 08-02-2001, 01:10 AM   #5
NASIOC Supporter
Member#: 246
Join Date: Sep 1999

Hey remember I told you I was doing these exact parts like 2 months ago? Well I should have them in next week. So I'll report how they work with this kit (remember I have the same thing as you).
Ethan is offline   Reply With Quote
Old 08-02-2001, 05:30 AM   #6
Scooby Newbie
Member#: 7680
Join Date: Jun 2001
Location: Far away
Thumbs up Change 'em together

Its a shame if you need to change clutch but not wanting to lighten the flywheel. Rev faster is the advantage, rocket ship!! vroom vrooooommm.......... go go go !!!

(loosing some low end torque is the dis-advantage , but i still opt for lightening it)


Last edited by Hyperex; 08-02-2001 at 05:33 AM.
Hyperex is offline   Reply With Quote
Old 08-02-2001, 08:09 AM   #7
HRE | giulio
Former Vendor
Member#: 481
Join Date: Nov 1999
Location: NY USA

That combo makes the car a lil harder to drive.
The ACT just wants to grab, and the lightened flywheel makes the car want to stall. So you gotta baby the clutch from a standstill. Get set for bucking until you relearn it.
Once it's moving though it's great!
HRE | giulio is offline   Reply With Quote
Old 08-02-2001, 09:10 AM   #8
Scooby Specialist
Member#: 3257
Join Date: Dec 2000
Location: Houston, TX
2000 ImprezaRS
Blue Ridge Pearl

Default My 2 cents...

A heavy flywheel will allow you to store energy. If you are at a standstill and you rev up the motor to like 4000 RPM and "dump" the clutch, you will launch very hard because of the stored up energy in the flywheel. However, with a light weight flywheel, if you let out the clutch at lower RPM and then floor it, you will be able to accelerate quicker because the power from the engine is not having to turn a heavy mass. More power is directly transfered to the wheels. I don't know if that helps any or not. A lighter flywheel will allow the engine to rev faster and have better throttle response. A heavy flywheel is easier to drive and can make the car launch harder. I think if you had the EXACT same car and ran a quarter mile with a heavy and a light flywheel, the light flywheel car would be a little quicker. Also keep in mind that a lighter flywheel takes weight off of the car as well. Removing 15lbs of weight anywhere from the car helps some. Removing it from a rotating mass helps even more. One more note: I think a heavy flywheel improves idle quality some and prevents stalling when you let the clutch out. If you had a RIMMER super-charger on your car, I don't think it would even idle with a light weight flywheel. Having said all that, I am getting the 12lb chromemoly flywheel and Kevlar clutch...

Last edited by subarumantoo; 08-02-2001 at 11:34 AM.
subarumantoo is offline   Reply With Quote
Old 08-02-2001, 09:13 AM   #9
Scooby Specialist
Member#: 80
Join Date: Jul 1999

it pretty much comes down to how streetable you want your car to be.

a lighter flywheel will make it harder to idle smoothly too if you get too light, so keep that in mind. also, a grabby clutch + lighter flywheel = lots of fun in stop and go traffic.

I have a STi clutch and flywheel, works great. The flywheel is about half the weight of a stock RS flywheel, around 13 lbs of so.

efoo is offline   Reply With Quote
Old 08-02-2001, 12:24 PM   #10
Scooby Specialist
Member#: 1257
Join Date: Apr 2000
Location: In the Valley.....Somewhere...
2000 GC8 WRX
93 RS-W Wagon (White) RIP


Hi all,

I just had a Jun Flywheel (12.34 lbs) and ACT clutch installed. I have not seen any negative side effects to the combination. The car idles just spot on. As for driving in heavy traffic, I would say that was not much of a prob as some say it would be. I learned from the first start to ease the clutch out.....while giving a little more gas. I have yet to stall the car, or even to cause it to jerk. Just don't try to lift off the clutch pedal so fast and everything is ok (that is only for first.....no problem once the car is moving)

As for loss of low down torque.....I have noticed no ill effect, infact I could say that it pulls even harder down low. But I must mention that I do not rev the car up when I take off. I tend to start out at about 2000-2500 rpm when going from a start...so I guess the lightened flywheel just complements my driving practices.

All I can say is "get it, if you don't like it, replace it" I kept my stock flywheel JUST in case. But now I think I'll make it into a base for my garage chair. ITS HEAVY ENOUGH!

Cheers All

Scoobie Newbie, now, tomorrow, and when I die.
EddyRS is offline   Reply With Quote
Old 08-04-2001, 02:23 AM   #11
ImprezaRS dot com
over boosted again
Member#: 1458
Join Date: May 2000
Chapter/Region: RMIC
Location: Colorado Springs CO USA
2015 Forester 2.0 XT
2005 2.5 RS, 2013 Tribeca


Get the flywheel now while the tranny will be out, it will save you money in the long run, and will really improve performance.


1) I ran gtech pro times stock with only GanzFlow intake before my turbo at a consistent 16.7 @ 84 (a stock RS is about a 17.5 - 18.0 here at 6,000 feet)

2) Then I did the JC Sports GB turbo kit with small IHI compressor and ran a 15.1 @ 94 at 5 psi boost.

3) Two weeks later I did a 12lb flywheel and ACT clutch and ran a 14.65 @ 97.5 with the same basic turbo kit.

Remember, at 6,000 feet an NA car will be about 1.5 - 2.0 seconds slower in the qtr than at sea-level. A turbocharged car, which compensates better for altitude, is still about 0.5 seconds slower up here than at sea-level. Whatever the case, the flywheel and clutch took off 1/2 second on the qtr mile times!

ImprezaRS dot com is offline   Reply With Quote
Old 08-04-2001, 09:58 AM   #12
Scooby Guru
Member#: 4418
Join Date: Feb 2001
Chapter/Region: South East
Location: Marietta, Georgia
2014 Golf GTI


Originally posted by efoo
it pretty much comes down to how streetable you want your car to be.

a lighter flywheel will make it harder to idle smoothly too if you get too light, so keep that in mind. also, a grabby clutch + lighter flywheel = lots of fun in stop and go traffic.

I have a STi clutch and flywheel, works great. The flywheel is about half the weight of a stock RS flywheel, around 13 lbs of so.

What is the sti flywheel made of?, and where can you get it?

Blindeye_03 is offline   Reply With Quote

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
stock seat belts and flywheel and oem clutch disk and drivers glass portangelessubie NWIC Private Classifieds 6 04-06-2010 12:28 PM
fidanza flywheel, sbc turbo kit, downpipe crossfire dukeduster Private 'For Sale' Classifieds 10 04-27-2006 10:10 PM
OEM Audio system and Flywheel and OEM stuff + Jdm goodie Sevaru Private 'For Sale' Classifieds 8 03-21-2006 10:58 AM
FS: Exedy clutch and flywheel, and more Crash477 Private 'For Sale' Classifieds 8 03-16-2005 04:47 PM
STi turbo flywheel and clutch $1 on eBay (Used 600 miles) Jude DeMeis Private 'For Sale' Classifieds 4 07-13-2004 12:27 PM

All times are GMT -4. The time now is 02:23 PM.

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.