[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Lightened Flywheels



Ron:
What you say is correct, but at no time did I even consider the scenario
of downshifting without matching revs.=20
If you match revs on downshift the transient effect you refer to is not
present and the engine has slightly better braking with a lighter
flywheel.
Dan

Ron Pieper wrote:
>=20
> I disagree...engine braking would be hindered by NOT having the
> flywheel helping to maintain the existing RPM.  Having the engine
> quickly drop revs *decreases* the effect of engine braking - it would
> provide little resistance.  Example:  imagine a massive flywheel - 5'
> diameter - ...if you have a given car speed, and drop a gear and
> release the clutch, your engine braking effects will be significant
> since the engine *won't* easily change revs to match the car/gear.  If
> you have a tiny flywheel, the engine RPM can more easily change,
> reducing the effects of the engine's braking on car speed.  It's not
> the speed of the engine that provides braking, it's the engine's
> resistance to a change in speed (it's rotating mass, of which the
> flywheel is a part).
>=20
> Now, OTOH, engine braking is not something I do or recommend...I have a
> tool for that, it's the brakes!
>=20
> Ron
>=20
> --- Dan Bubb <jdbubb@ix.netcom.com> wrote:
> > Wait a minute! Why would there be less engine braking?
> > The braking effect of the engine is not changed by lightening the
> > flywheel (since engine braking is a function of the engine trying to
> > pump air against a closed throttle) and the reduced inertia means the
> > engine revs will drop faster. As a matter of fact with the reduced
> > inertia there is less mass holding the engine revs up so the net
> > effect
> > is slightly (very slightly) MORE engine braking.
> > Dan
> >
> > Ken Bates wrote:
> > >
> > > Oooohh,  That is a good pont.  I would not have thought of that.
> > This mod
> > > would be on my "list" the next time I do a clutch.    I am a
> > "downshifter"
> > > when i am driving hard and this diminished effect would be missed.
> > Thank
> > > you for bringing that up.
> > > Ken
> > > '79 Scirocco 16v project "McFly"
> > > '86 16v (parts car)
> > > VORTEX:  "Indiana Red"
> > >
> > > ----- Original Message -----
> > > From: "Robert Piwonka" <tpiwonka@TTACS.TTU.EDU>
> > > To: "Scirocco" <scirocco-l@scirocco.org>
> > > Sent: Monday, March 25, 2002 2:32 PM
> > > Subject: RE: Lightened Flywheels
> > >
> > > > on stock cams I noticed no difference in idle characteristics
> > when I had
> > > the
> > > > Velocity lightened flywheel.  However donwshifts have less effect
> > ie. less
> > > > engine breaking and the car reved(sp) like a motorcycle ;)
> > > >
> > > > Robert Piwonka
> > > > 86 16V
> > > >
> > > > -----Original Message-----
> > > > From: scirocco-l-admin@scirocco.org
> > > > [mailto:scirocco-l-admin@scirocco.org]On Behalf Of Allyn
> > > > Sent: Monday, March 25, 2002 2:18 PM
> > > > To: Euroroc II; Brian Wagner; Scirocco-l@scirocco.org
> > > > Subject: Re: Lightened Flywheels
> > > >
> > > >
> > > > Heavy - slower acceleration, smooth idle
> > > > Light - lumpy idle, at an extreme you may have to raise idle
> > speed to
> > > > maintain idle without stall
> > > > Al
> > > >
> > > > ----- Original Message -----
> > > > From: "Euroroc II" <flaatr@yahoo.com>
> > > > To: "Brian Wagner" <scirocco_88_16v@hotmail.com>;
> > > <Scirocco-l@scirocco.org>
> > > > Sent: Monday, March 25, 2002 2:12 PM
> > > > Subject: Re: Lightened Flywheels
> > > >
> > > >
> > > > > So anyone want to clear up the pros and cons of lightening the
> > fly
> > > wheel?
> > > > > I've got a good idea of the advantages and disadvantages but
> > I'd like to
> > > > > get them confirmed.
> > > > >
> > > > > -Raffi
> > > > >
> > > > >
> > > > > At 12:07 PM 3/25/02 -0600, you wrote:
> > > > > >6 is extremely light, most of the lightened flywheels you buy
> > are
> > > 8.3lbs
> > > > > >that might be a better bet.
> > > > > >
> > > > > >Brian
> > > > > >
> > > > > >
> > > > > >>From: "Sal Guzzo" <pellom@YorkU.CA>
> > > > > >>To: "Scirocco" <scirocco-l@scirocco.org>
> > > > > >>Subject: Lightened Flywheels
> > > > > >>Date: Mon, 25 Mar 2002 12:20:57 -0800
> > > > > >>
> > > > > >>Hi all,
> > > > > >>
> > > > > >>I wanna lighten my flywheel but I'm not sure how much to take
> > off.
> > > It's
> > > > a
> > > > > >>210mm flywheel for an 8V.  I think that it weighs about 12
> > pounds now
> > > > and I
> > > > > >>was thinking of having it reduced to about 6 pounds.  Is that
> > kewl?
> > > > > >>
> > > > > >>TIA
> > > > > >>
> > > > > >>Sal
> > > > > >>
> > > > > >>
> > > > > >>_______________________________________________
> > > > > >>Scirocco-l mailing list
> > > > > >>Scirocco-l@scirocco.org
> > > > > >>http://neubayern.net/mailman/listinfo/scirocco-l
> > > > > >
> > > > > >
> > > > >
> > >_________________________________________________________________
> > > > > >Chat with friends online, try MSN Messenger:
> > http://messenger.msn.com
> > > > > >
> > > > > >
> > > > > >_______________________________________________
> > > > > >Scirocco-l mailing list
> > > > > >Scirocco-l@scirocco.org
> > > > > >http://neubayern.net/mailman/listinfo/scirocco-l
> > > > >
> > > > >
> > > > > _________________________________________________________
> > > > > Do You Yahoo!?
> > > > > Get your free @yahoo.com address at http://mail.yahoo.com
> > > > >
> > > > >
> > > > > _______________________________________________
> > > > > Scirocco-l mailing list
> > > > > Scirocco-l@scirocco.org
> > > > > http://neubayern.net/mailman/listinfo/scirocco-l
> > > >
> > > >
> > > > _______________________________________________
> > > > Scirocco-l mailing list
> > > > Scirocco-l@scirocco.org
> > > > http://neubayern.net/mailman/listinfo/scirocco-l
> > > >
> > > >
> > > > _______________________________________________
> > > > Scirocco-l mailing list
> > > > Scirocco-l@scirocco.org
> > > > http://neubayern.net/mailman/listinfo/scirocco-l
> > > >
> > >
> > > _______________________________________________
> > > Scirocco-l mailing list
> > > Scirocco-l@scirocco.org
> > > http://neubayern.net/mailman/listinfo/scirocco-l
> >
> > _______________________________________________
> > Scirocco-l mailing list
> > Scirocco-l@scirocco.org
> > http://neubayern.net/mailman/listinfo/scirocco-l
>=20
> =3D=3D=3D=3D=3D
> Cheapass Ron
> "Victor" '87 16V Scirocco
> "Teufelhasen" '93 Cabby <-For sale
>=20
> If it ain't foggy, TURN OFF YOUR FOG LIGHTS.
>=20
> __________________________________________________
> Do You Yahoo!?
> Yahoo! Movies - coverage of the 74th Academy Awards=AE
> http://movies.yahoo.com/