MPG with AC on - 92 Civic AT

AAAAaaaaaaaaaaarghhhhhhh!

I drained the tank, topped it off, hit the trip reset and started my
experiment. I drove down the tank until darn near empty using the air
conditioner on recirc for the entire tankful. Last night the little
lady ran some errands and put $10 in to get her around! See what a lack
of communication with the spouse causes, you youngsters?

Anyway, I usually average maybe just under 300 miles before refilling,
but with the air on I was right around 200. That's quite a big hit for
the air. My guess is that with the drop in HP with the compressor
running, I tended to floor it a bit more. I ususally am a right-laner
driving the Civic (like what other choice do I have?), but the leadfoot
level went up running the air. I found myself flooring it forcing a
downshift more often. Leadfoot level went up to around a 7-8 out of 10.
IIRC some manufacturers tout a 5-10% drop in fuel economy with the air
on, but I saw quite a bit more drop, albeit somewhat unscientific in
method.

Thoughts?

 

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For the sake of facts, it's good to lose the word 'tank' and substitute
the actual volume of fuel, either gallons, litres, whatever. Otherwise,
it's kinda like hearsay, or gossip.

There's only one correct way to explain fuel mileage: How much fuel was
used to go how far.

'Curly'

 

For the sake of facts, it's good to lose the word 'tank' and substitute

Totally agree. I just wish I would've let the boss know about the
experiment before she put gas in. My figures from last week had to be
estimated.

 

I've got a 98 Civic with no Air and Standard tranny, which can easily get
over 400miles/tank.
My wife has same model Civic, but equipped with Automatec and Air. With the
Air running, She can make 300 miles/tank, on a good day. The current 05 1.7L
Civic will return even better mileage in a heavy load situation. The extra
..1L has a negligent effect on all out performance, but it does make for good
efficiency when the car is loaded at low revs.

The nice thing about a small displacement engine, is that they return
excellent mileage when they're not loading down. But, once you put too much
of a load on them (which is easy to do), they'll put an alcoholic to shame.

Case Study; Mercedes Smart car, it's half the size/weight as my Hatch and
has a tinny diesel engine to boot, but fuel consumptions is only 27% better
then my Civic. Granted, my Civic would need to idle under 3000rpm to achieve
the great mileage (which isn't a problem since thecar has enough torque so
that the low rpm is adequate for normal driving...plus Toronto is a flat
area). Meanwhile the Smart is going all out just to maintain a mundane
130km/hr (while at that speed my Hatch is coasting along at under 3000rpm).
Unlike the Smart, I can charge against the wind at 190km/hr, which might not
be smart, but it is cool.

Pars