"Adrian" wrote in message
. 1.4...
scott ) gurgled happily, sounding much like they were
saying :

Try this for a laugh, swim 10 lengths as fast as you can, then 10
lengths quite slowly. Which one do you think you've used most energy
for?

I know cars are very different

Erm, yes.

but you still have the basic mechanics of pushing an object
through a fluid at speed.

I don't often drive through "fluid", and my car has more than one gear.

A fairer example would be cycling.

Cycle ten miles, on the flat, at a certain pedal cadence (engine rpm) in
a low gear.

Now cycle ten miles, on the flat, at the same pedal cadence (engine rpm)
in a higher but still comfortable gear.

See the point yet?

Yes, the second is far far better for you.
There will be lower forces on legs and muscles.

If you're cruising (low throttle opening) in a car in a highish gear, at
low revs, that's bound to emit less pollution for a given journey than
similar revs in a lower gear at lower speed - because those revs are
being used for far less time.

This assumes the same throttle position.
In all but the slowest of speeds (see below), this will not be the case.

Assuming the engine's running fairly light
loads, the emissions per minute will be close enough to equal to make no
difference, but if you do the journey in half the time....

The speed where this happens is far from obvious.
As I stated elsewhere, the only place I have seen such things discusses was
by people who loved their monstorous 4x4s

W K ) gurgled happily, sounding much like they were
saying :

As I stated elsewhere, the only place I have seen such things
discusses was by people who loved their monstorous 4x4s

*Bzzzzt*

I can't stand "monstrous 4x4s"

"Adrian" wrote in message
. 1.4...
W K ) gurgled happily, sounding much like they were
saying :

As I stated elsewhere, the only place I have seen such things
discusses was by people who loved their monstorous 4x4s

*Bzzzzt*

I can't stand "monstrous 4x4s"

Discussed by people who seemed to be quoting actual figures or research.