Good point John.

I don't really know where you'd start in terms of figuring out the flow at
idle with the throttle valve closed. Maybe with a UniSyn? Or would that only
give a vacuum reading?

Either way you're going to be getting hours per gallon.

On Nov 25, 2007 12:06 AM, John Connolly, Aircooled.Net <john@aircooled.net>
wrote:

> but we have a throttle limiting the amt of air entering the engine (unless
> you have a diesel).
>
> John
> Aircooled.Net Inc.
>
> ----- Original Message -----
> From: "mike elliott" <camping.elliott@GMAIL.COM>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Saturday, November 24, 2007 5:26 PM
> Subject: Re: Calculate fuel consumption when idling?
>
>
> > Do you win? Heck, I don't know. I'll take a shot at it. Watch me get
> > it spectacularly wrong.
> >
> > The 1.9L engine has 475cc displacement per cylinder. I think two
> > cylinders fire per revolution, so at 900 rpm we got 900 x 2 x 475 =
> > 855cc of air per minute being sucked into the engine. If the mixture
> > is a good stoichiometric one, we'd have about a 1:15 fuel:air mass
> > ratio. Air has a mass of 1.3g per liter, so that's .855 x 1.3 = 1.1kg
> > of air per minute, with being one-fifteenth of that, or 74g per
> > minute. At 60 minutes that's 4.4kg of fuel. Gasoline masses roughly
> > 740 grams per /liter, so that's 6 liters, roughly 1.6 gallons U.S. per
> > hour.
> >
> > Those are the numbers I come up with and I bet they're within an order
> > of magnitude of being right.
> >
> > Mike "Rocket J Squirrel" Elliott
> >
> > On Nov 24, 2007 3:52 PM, Matthew Snook <matt@snooksband.com> wrote:
> > > 0.9375?  Is that right?  Do I win?
> > >
> > > :)
> > >
> > > At 60mph, mine's turning @ 3200rpm.  It will burn 3 gallons doing
> that.
> 3
> > > gallons per hour at 3200rpm.  But it idles at 1000rpm.  So that comes
> to
> > > 0.9375 gallons per hour at 1000rpm.  Of course there's no wind
> resistance at
> > > that speed, so maybe less...
> > >
> > > Matthew Snook (@ ~3000 ft)
> > >
> > >
> > >
> > > -----Original Message-----
> > > From: Michael Elliott
> > > Subject: Calculate fuel consumption when idling?
> > >
> > > A properly-tuned 1.9L WBX engine would consume how many gallons of
> > > gasoline per hour when idling at sea level? Would this be
> significantly
> > > different at 6,000 feet?
> > >
> > >
> >
> > !DSPAM:4748b1c081151569112627!
> >
> >
>

--
Jake
1984 Vanagon GL
1986 Westy Weekender "Dixie"
Crescent Beach, BC
www.crescentbeachguitar.com
http://subyjake.googlepages.com/