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Dave Plowman (News) Dave Plowman (News) is offline
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Default The physics of cars - a question sequence.

In article ,
Clive George wrote:
On 31/03/2016 00:43, Dave Plowman (News) wrote:
In article , Clive
George wrote:
We're not talking 0-60 times here. Just the best rate of change of
speed.


Ok. Which is achieved with the gear chosen so the engine at its
maximum power, not maximum torque.


You should join Turnip in some basic mechanical theory lessons.


The weird thing is you've just agreed with my statement in your previous
post.


At a given road speed, the maximum rate of change of road speed will
be achieved at the engine's maximum power point. The necessary gear
ratio to achieve this will be determined by the chosen road speed
and the engine's maximum power speed.


is a longer way of saying what I've just said, and you replied saying
"Yes".


Why agree with one yet disagree with the other?


Sigh. If you measure the time taken for say 5 mph increments in speed in
any one gear, the shortest time will be at peak torque. Not peak BHP.

You decided to choose a road speed where the engine was at peak BHP in
that gear. The only way to get the same road speed at peak torque would be
by using a higher gear, since peak torque is always at lower RPM than peak
BHP.

--
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Dave Plowman London SW
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