Jason Sawyer wrote:
>
> Paul Hunt wrote:
>
> > Jason Sawyer wrote:
> > >
> > > Why 3rd? I use reverse, that way when I push the car backwards, the
>engine spins
> > > the proper way. Is it easier to move in 3rd? Seems like it would be
>harder, but
> > > maybe I'm just an idiot. (You out there, J.B.?)
> > >
> > > Jason
> >
> > Hi Jason, no offence but you *are* an idiot. When you are driving in
>reverse (or
> > first) think how many times the engine revolves for a given distance covered
> > compared to 3rd. Now imagine pushing the car the same distance in each
>gear. You
> > have to rotate the engine many more times in reverse than in third,
>therefore
> > reverse must be harder.
> >
> > Cheers,
> > PaulH.
>
> Well then, why not use 4th? Sure, the engine moves more (higher RPMs) in
>1st as
> opposed to 3rd, but isn't it doing less work (in 1st)? Sure it might be
>faster to get
> the engine to the next valve in a higher gear, but is it really easier? If I
>push my
> car two feet in 1st, and the engine turns over once (just an example) then
>I'm using X
> amount of force. Now, if I push my car two feet in 3rd and the engine turns
>over five
> times (again with the example) then isn't it true that I'm using 5X force?
>
> Jason
We're confusing harder with faster here. 1st is quickest at turning the engine
(in terms of
distance pushed) but is hardest (in terms of effort). 4th is slowest at
turning the engine
(in terms of distance) but easiest (in terms of effort). 3rd is a compromise
where it is
fairly easy to push but turns the engine to the next valve fairly quickly.
You also have the gearing the wrong way in comparing distance pushed with
number of revs in
each gear. You will turn the engine over more times in first for a given
distance than you
will in 4th, that is why it is harder to push a car in gear in 1st than it is
in 4th. Don't
forget that when you are pushing a car in gear the gearing works in completely
the opposite
way to when the engine is pushing the car.
PaulH.
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