On Fri, 16 May 2008 21:27:22 +0100, Orchid XP v8 wrote:

> Jim Henderson wrote:
> 
>> There isn't a linear relationship between the rotational speed of the
>> wheels and the speed of the engine.
> 
> Well that's news.
> 
>> If I take my foot off the gas, the engine revs drop.  The car may or
>> may not slow down (depending on the road and the landscape).
> 
> Not true. The engine revs depend on the speed of the vehicle.
> 
> If you don't believe me, try rolling down a hill at 30, and then stick
> the car into 1st gear. Watch the revs go through the roof, even though
> you haven't touched the gas.
> 
>> Similarly, if I apply the brakes to a full stop, the engine doesn't
>> die, it idles.
> 
> Um, yes it does. Unless...
> 
>> Then of course if you put the car in neutral, you've completely
>> disengaged the engine from the wheels.
> 
> ...you disenguage the engine from the wheels. Then there really isn't
> any relationship. But as long as the car stays in the same gear, there
> is a fixed relationship.

Perhaps in a manual transmission - in my automatic, though, I'll stick 
with what I indicated....I s'pose I could ask my father-in-law when I 
talk to him next, since his life's work has been working on cars....

Jim

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