Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

 
 Reply to this topicStart new topic
> Lightened flywheel and streetability?, I like the idea unless it's a PITA to drive
Cheapsnake
post Nov 26 2008, 08:40 AM
Post #1


Member
**

Group: Members
Posts: 419
Joined: 15-November 07
From: Door County, WI
Member No.: 8,341
I've changed my plans for a V8 conversion and decided to stay with a hopped up 2.0 instead. I'm considering a lightened flywheel since my impression of these engines is that they're somewhat doggy off idle. The drawback, of course is that standing starts become more of a challenge due to the lack of "flywheel effect".

In a competition environment this isn't much of an issue because hopefully you only have to do it once, but in a driver, especially in city traffic this could be an issue if you have to rev the engine and slip the clutch every time you want to get under way. Anyone got any experience with lightened flywheels in a 2.0 and want to shine some light on the issue?

Tom
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Root_Werks
post Nov 26 2008, 08:49 AM
Post #2


Village Idiot
*****

Group: Members
Posts: 8,319
Joined: 25-May 04
From: About 5NM from Canada
Member No.: 2,105
Region Association: Pacific Northwest
The lighter your flywheel and the bigger displacement your engine is, the rougher it will idle.

Also, if you have a high torque starter and aluminum flywheel be careful. I had a starter knock a couple teeth off the flywheel.

If you don't go too light, thier great for street cars.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Bleyseng
post Nov 26 2008, 09:23 AM
Post #3


Aircooled Baby!
**********

Group: Members
Posts: 13,034
Joined: 27-December 02
From: Seattle, Washington (for now)
Member No.: 24
Region Association: Pacific Northwest
depends on how much lbs is taken off. Mine just revs up faster....
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Cheapsnake
post Nov 26 2008, 09:25 AM
Post #4


Member
**

Group: Members
Posts: 419
Joined: 15-November 07
From: Door County, WI
Member No.: 8,341
QUOTE(Root_Werks @ Nov 26 2008, 06:49 AM) *


Also, if you have a high torque starter and aluminum flywheel be careful. I had a starter knock a couple teeth off the flywheel.



Ouch! I've always wondered why, when a flywheel and starter gear clash it's always the difficult change-out flywheel that takes the hit rather than the easy change-out starter. Thanks for the response.

Tom
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Cheapsnake
post Nov 26 2008, 09:27 AM
Post #5


Member
**

Group: Members
Posts: 419
Joined: 15-November 07
From: Door County, WI
Member No.: 8,341
QUOTE(Bleyseng @ Nov 26 2008, 07:23 AM) *

depends on how much lbs is taken off. Mine just revs up faster....


do you have any machining specs?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
r_towle
post Nov 26 2008, 09:37 AM
Post #6


Custom Member
***************

Group: Members
Posts: 24,574
Joined: 9-January 03
From: Taxachusetts
Member No.: 124
Region Association: North East States
Flywheel lightening is not a black art...its actually pretty straight forward.

Our flywheels are unique in one aspect. The measurement and relationship between the flange that the pressure plate bolts to and the flywheel friction surface needs to remain within specs...

I have seen many super light flywheels with a majority of the material between the pressure plate mounting bolts removed.

You get to light and you need to feather the gas pedal at idle just to keep in running.
11 Lbs is probably the limit of how low I would suggest on a street/autox car.
8-9lbs is on a race car with a race clutch.

I believe the stock flywheel is around 16lbs.

Rich
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Chris Hamilton
post Nov 26 2008, 09:41 AM
Post #7


Senior Member
***

Group: Members
Posts: 611
Joined: 7-March 06
From: Berkeley, CA
Member No.: 5,687
My flywheel is about 10lbs, and I have a sachs aluminum pressure plate. Pretty nice for street driving.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
914werke
post Nov 26 2008, 10:45 AM
Post #8


"I got blisters on me fingers"
**********

Group: Members
Posts: 10,057
Joined: 22-March 03
From: USofA
Member No.: 453
Region Association: Pacific Northwest
Plug .. Flywheel FS (IMG:style_emoticons/default/wub.gif)
User is online!Profile CardPM
Go to the top of the page
+Quote Post
r_towle
post Nov 26 2008, 11:02 AM
Post #9


Custom Member
***************

Group: Members
Posts: 24,574
Joined: 9-January 03
From: Taxachusetts
Member No.: 124
Region Association: North East States
QUOTE(rdauenhauer @ Nov 26 2008, 11:45 AM) *

Plug .. Flywheel FS (IMG:style_emoticons/default/wub.gif)

I also have one that I have tried to sell over the years.....and your plug is a shameless plug...but a great price for the poster...go get that one..is cheaper than the machine work to lighten it.

Rich
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Borderline
post Nov 26 2008, 11:12 AM
Post #10


Senior Member
***

Group: Members
Posts: 720
Joined: 8-February 05
From: San Juan Bautista, CA
Member No.: 3,577
Region Association: Northern California
I have a lightened flywheel on my 1911 and it drives great! I highly recommend it! (IMG:style_emoticons/default/driving.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Cheapsnake
post Nov 26 2008, 11:29 AM
Post #11


Member
**

Group: Members
Posts: 419
Joined: 15-November 07
From: Door County, WI
Member No.: 8,341
Thanks for the offers guys, but I've got a new multi-purpose machine that I've just got to use on the one I've got. Then, after I totally f**k that one up I'll be in touch. (IMG:style_emoticons/default/confused24.gif)

Tom
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Mark Henry
post Nov 26 2008, 12:01 PM
Post #12


that's what I do!
***************

Group: Members
Posts: 20,065
Joined: 27-December 02
From: Port Hope, Ontario
Member No.: 26
Region Association: Canada
Do not take weight off of the backside of the friction surface.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
hydroliftin
post Nov 26 2008, 12:04 PM
Post #13


Member
**

Group: Members
Posts: 373
Joined: 8-November 06
From: Vallejo, CA
Member No.: 7,180
Region Association: Northern California
Tom,

When I rebuilt my 2.0 I had the machinist lighten the stock flywheel. Not sure how much was taken off, but not extreame. I have not noticed any issues with getting the car moving off the line, but it does rev easier. I would recomend it.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Cheapsnake
post Nov 26 2008, 12:08 PM
Post #14


Member
**

Group: Members
Posts: 419
Joined: 15-November 07
From: Door County, WI
Member No.: 8,341
QUOTE(Mark Henry @ Nov 26 2008, 10:01 AM) *

Do not take weight off of the backside of the friction surface.


Good to know, so everything off the friction surface?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
CliffBraun
post Nov 26 2008, 01:24 PM
Post #15


Member
**

Group: Members
Posts: 252
Joined: 26-April 06
From: San Luis Obispo,ca
Member No.: 5,933
Region Association: None
QUOTE(Chris Hamilton @ Nov 26 2008, 07:41 AM) *

My flywheel is about 10lbs, and I have a sachs aluminum pressure plate. Pretty nice for street driving.


Don't forget the clutch.... I have the same set up but with a KEP pressure plate and I love it. It rev's so nicely, I have no problem driving it even on my dying tranny.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
davep
post Nov 26 2008, 01:24 PM
Post #16


914 Historian
*****

Group: Benefactors
Posts: 5,141
Joined: 13-October 03
From: Burford, ON, N0E 1A0
Member No.: 1,244
Region Association: Canada
UH, no. Most is removed from the outer ring. The working surface needs it, and the more mass removed as far from the center as possible is better.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Mark Henry
post Nov 26 2008, 01:58 PM
Post #17


that's what I do!
***************

Group: Members
Posts: 20,065
Joined: 27-December 02
From: Port Hope, Ontario
Member No.: 26
Region Association: Canada
QUOTE(Cheapsnake @ Nov 26 2008, 01:08 PM) *

QUOTE(Mark Henry @ Nov 26 2008, 10:01 AM) *

Do not take weight off of the backside of the friction surface.


Good to know, so everything off the friction surface?


Do NOT take weight off of the backside of the friction surface.

You run the risk of warpage if you do.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Chris Hamilton
post Nov 26 2008, 02:26 PM
Post #18


Senior Member
***

Group: Members
Posts: 611
Joined: 7-March 06
From: Berkeley, CA
Member No.: 5,687
QUOTE(Mark Henry @ Nov 26 2008, 11:58 AM) *

QUOTE(Cheapsnake @ Nov 26 2008, 01:08 PM) *

QUOTE(Mark Henry @ Nov 26 2008, 10:01 AM) *

Do not take weight off of the backside of the friction surface.


Good to know, so everything off the friction surface?


Do NOT take weight off of the backside of the friction surface.

You run the risk of warpage if you do.



Of if anyone wants to go that route I've got one pre-warped they can buy, save themselves the trouble of mounting it and having to warp it themselves. (IMG:style_emoticons/default/confused24.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
« Next Oldest · 914World Garage · Next Newest »
 

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 

Display Mode: Standard · Switch to: Linear+ · Switch to: Outline

Track this topic · Email this topic · Print this topic · Subscribe to this forum

- Lo-Fi Version Time is now: 12th May 2024 - 01:05 AM
Invision Power Board v9.1.4 © 2024  IPS, Inc.
All rights reserved 914World.com © since 2002
914World.com is the fastest growing online 914 community!
We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ...