Date: Sat, 15 Sep 2001 00:56:36 -0500
Reply-To: Max Wellhouse <maxjoyce@IPA.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Max Wellhouse <maxjoyce@IPA.NET>
Subject: Re: Ideal Gearing Query For Subaru Vanagons
Content-Type: text/plain; charset="iso-8859-1"
Anybody studied what Subaru used to begin with? Reinventing the wheel is
fun to talk about, though.
DM&FS
----- Original Message -----
From: "Todd Last" <Rubatoguy@MINDSPRING.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, September 14, 2001 9:15 AM
Subject: Re: Ideal Gearing Query For Subaru Vanagons
> Personally, I like my cruising RPM as close to 3,500 RPM as possible.
>
> However,
> I'd say the best RPM for cruising speed also depends on:
> Where the torque peak is on the motor,
> The torque curve of the motor,
> and the 4th gear ratio.
>
> If you can easily shift to 4th for "passing" then you may want to have a
tall
> (low rpm) 5th to go for top MPG and low engine wear. However, if you have
to
> depend on 5th for passing and hills, you probably do not want to go too
tall.
> The torque characteristics play into this as well.
>
> You might want to check the web for some calculators.
> Here is one that will calculate your best shift points (for the best
> acceleration):
>
> http://www.prestage.com/carmath/dynochart.asp
>
> I have not keyed in the Vanagon info - it would be interesting to see what
it
> said.
>
> Todd
>
> '88 Westy
>
> Derek Drew wrote:
>
> > I have been approached on numerous occaisions by Vanagon owners asking
what
> > the ideal gearing setup for Subaru powered Vanagons. My interest is
> > primarily syncros, but I think much of what is said about gearing for
4WD
> > also applies to 2WD.
> >
> > The key question that must be answered, upon which all gearing advice
> > depends, is what rpm the vehicle should have at 76mph (working top speed
> > given the speed limits). That is, what is the rpm that you would be
> > comfortable with at 76mph?
> >
> > If you set the rpms too high, you annoy the passengers in the vehicle
and
> > possibly extra wear on the motor. If you set the rpms too low, then you
> > have a loss of power and torque.
> >
> > In the non-subie stock Vanagon with a slight power boost through ratio
> > rockers and computer chip upgrade, I believe the desirable figure is
76mph
> > at 4,000 rpm (compared with ~71mph in stock form). But I have heard
> > comments from subie owners complaining about high rpms, and I am under
the
> > impresssion that subie owners would prefer to set this number lower --
say,
> > 3500 rpms at 76mph, or even lower. How low I just do not know.
> >
> > This email is a general query to subie owenrs who drive in non-flat
areas
> > of the country to send me an email saying what they judge the best
gearing
> > out come in 4th gear would be, given your experiences. I need emails
that
> > explain "I think we should be at x rpm at x mph in 4th gear.)
> >
> > This information will later be used to construct tables of desirable
> > outcomes that other drivers will use in the future when planning their
> > gears and placing gear orders.
> >
> > If you have a great deal of clarity about the lower gears as well, I can
> > accept that data too, but my primary interest is in the 4th gear.
> >
> > _______________________________________________
> > Derek Drew
> > CEO & Co-Founder
> > http://www.ConsumerSearch.com/
> > New York, NY
> > ===========================
> > "Best Expert Review Site"
> > for product reviews on the Internet
> > Jan. 2001, PC World Magazine
> > ==========================
> > derekdrew@rcn.com
> > 212-580-6486
> >
> > Alternate numbers for the industrious phone caller that wants to try
every
> > avenue: 212-580-6486 (best), 917-848-6425 (cell); 202-966-7907 (Work),
> > 212-580-4459 (Home), 202-966-0938 (Home), 978-359-8533 (fax [efax]),
> > 212-269-3188 (New York Seaport office).
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