Andy Ramm wrote:
> Simple mathematics and physics, as well as personal experience bear witness
>to a
> contradictory opinion. IMHO, YMMV, ODISBETTER.
With regards to fuel mileage or wear?
Here's a "fuel mileage" thought. To cruise at 80mph with the
aerodynamics of a B might require, say, 50hp.
It still requires 50hp no matter what gear you are in.
This 50hp must come from burned fuel. In order to generate
50hp from fuel you must burn X quantity of fuel with some
constant caloric factor and Y efficiency.
Horsepower is therefore a function of fuel consumed and
efficiency.
The goal then to get the best mileage is to run the engine at
the speed which it is most efficient. What speed that actually
IS depends on the engine itself.
For a typical piston engine, you could make a case that this
would tend to favour the lower RPMs because it wastes less
energy in accelerating and decelerating the reciprocating
piston mass, but that's not what I'd call a "complete"
analysis.
Hmmm... I'm just trying to raise more questions, not
answer them. I would like to disprove the attitude that
"it's obvious" though. It's not.
--
Trevor Boicey, Ottawa, Canada.
tboicey@brit.ca, http://www.brit.ca/~tboicey/
[ Seeking some miscellaneous MG parts, see the list on the web page... ]
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