Date: Sun, 27 Aug 2000 17:12:06 -0400
Reply-To: Lawrence Johnson <larry_avery.johnson@sympatico.ca>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Lawrence Johnson <larry_avery.johnson@sympatico.ca>
Subject: Re: Better Mileage Anyone? (without going ala Lilley)
Content-Type: text/plain; charset=us-ascii
Mark,
I'm no mechanic but I don't think that "hot spark" is the point here. The
important thing is the fuel burn rate and timing.
A later spark and slower burn will run cooler because of the heat consumed in
vaporizing the fuel. The torque should be higher but the acceleration lower.
This is what I have found with the Bosch 4 prong plugs that we installed about 3
months ago. However, my gas consumption has not changed from my previous
experience with Bosch Platinums.
-Larry
'86 Syncro Westfalia
Mark Dorm wrote:
> The heat (that isn't converted to motion) is still lost energy - its a lack
> of efficiency - its energy released from the fuel that moves out into the
> environment - I forget but isn't a gas engine only about 40 or 60 percent
> efficient in its transfer of energy from fuel to motion - wouldn't we better
> off measuring the speed of the piston upon explosion - and if theres an
> upper limit for how fast a particular piston can move then won't a hotter
> spark (that goes beyond that limit) just result in more heat being lost to
> the system
>
> >From: CHRIS STANN <cstann@home.com>
> >
> >Mark Dorm said:
> >
> > > We're not interested in creating heat - we're interested in moving the
> > > pistons - the heat is really a loss of energy
> >
> >Well, don't they call it the internal COMBUSTION engine? The engine is
> >nothing but a heat pump, so your comment is absurd. *** Heat is energy!
> >***
> >Heat is released during combustion. The stored energy in gasoline is
> >released as heat. Combustion is nothing but accelerated oxidation. You're
> >burning fuel. So you are interested in making heat, it's what moves the
> >pistons. I've never heard of a cold explosion.
> >
> >What you're not interested in is making more heat than your engine can
> >safely disperse and move away from precious mechanical parts.
> >
> >All I was saying is that the hotter heads may be explained by a more
> >complete combustion. This does not leave enough unburned fuel to cool
> >things inside the combustion chamber. So the plug that gives you hotter
> >heads may actually be better, in strict technical terms, but not better for
> >your engine.
>
> _________________________________________________________________________
> Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
>
> Share information about yourself, create your own public profile at
> http://profiles.msn.com.
|