In article ,
Roger Mills wrote:
On 30/03/2016 18:39, Dave Plowman (News) wrote:


We're not talking 0-60 times here. Just the best rate of change of
speed. No vehicle with an IC engine gives a linear rate of increase in
speed from 0 to top speed. It will obviously produce the best
acceleration in the lowest gear, slightly less in the next one up, and
so on. But that is a red herring as regards when the engine produces
the best acceleration in any one gear.


OK, can we agree on this?

In a given gear, the maximum rate of change of road speed will be
achieved at the engine's maximum torque speed. The road speed at which
that occurs will be determined by the engine speed and the gearing.

Yes.

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.

Yes. Assuming you have a gear which allows that road speed at maximum BHP.
That would by nature be a lower gear than one which place the engine at
peak torque at that road speed. And a lower gear multiples the torque.

Yes or no please - no equivocation!

Doesn't need any equivocation. Of course a lower gear multiplies the
engine's torque.

--
*Acupuncture is a jab well done*

Dave Plowman London SW
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