balancing.

[mr.utility at highstream.net (David Utley)]

-----Original Message-----
From: T. Reed [mailto:treed2@wsu.edu]
Sent: Sunday, November 02, 2003 5:00 AM
To: David Utley
Cc: Mark; 'Dan Bubb'; scirocco-l@scirocco.org
Subject: RE: balancing.



"Tell me what's wrong with this argument:

When you climb a hill in a car, you're not going any faster, the road is
just more vertical. So, the acceleration at the flywheel is zero; it is
still moving at a constant speed. The engine is just working harder than
it was before you started climbing the hill, it's not spinning any faster
or slower.

Therefore I conclude that the flywheel weight has no effect when
climbing hills. This is based on our previous agreement that the flywheel
weight doesn't matter when you're moving at a constant speed."
Okay...  Here is another argument, as I cannot think of a way to work within
that one...
Two cars, going 70, side by side...  One is 2000lbs, the other is 3000lbs...
You two both approach a hill...  Neither one of you attempts to accelerate,
or to maintain the same speed...  Which one will go further up the hill?
This is the whole of my argument...  More spun weight carries more inertia,
which will, under some circumstances, benefit the driver...  Does that one
make sense?



"As far as driving up one side of a hill and then back down again, this is
similar to the braking energy explanation. You're storing potential energy
in the mass of the car as you drive up the hill. A car with a heavier
flywheel is just storing more energy on top of that. As you drive down the
hill you will have to use the brakes to dump the energy from the extra
flywheel mass as well as from climbing the hill."
Not necessarily...  Actually what happens at highway speeds is that you have
such wind-drag and friction forces working against you, that you would
instead of breaking, not have to have the throttle down nearly as much, you
coast more, which is again the benefit of the stock flywheel...



"Which brings up one more thing-- the fuel dumped in to the engine is
determined by the air flow plate position, not the throttle position."
Actually, it is the other way around...  If you take your foot of the
throttle at 70mph, and decelerate, there is no fuel entering the engine...
With your statement above, if that were true, then a lot of air would go
through/around the throttle butterflies, which it cannot do...  If it could
it would not do any good to have a butterfly there at all...
" If
your foot is off the gas and your engine is winding down it's still
getting fuel (albeit less than usual, at least with cis-e, because of
deceleration en-lean-ment) because the air flow plate is still lifted
even if the throttle body is closed. The engine spins down faster with a
light flywheel, thus more fuel savings."

The airflow plate is not lifted at coast at all...  Sorry to contradict you
here, after all your efforts...  :(  Thanks for the continued attempts to
understand...

David

-Toby