Top down / Windows Open / A/C weather or what??

paradigm said:
Without derailing this thread even more, yes generally my average over the last 1000 miles or so is 28.9MPG, but thats an AVERAGE of the last 1000 miles, including commuting, having a larf, general hooning about, everyting.

Its only you who gets pants MPG for no reason.

I get pants mpg? :confused:
 
Apparently AirCon reduces petrol consumption by 10-20%.

Hence, I don't use mine. Besides, if I did, I'd need to have the windows wound up and I'm muffle that gorgeous Alfa V6 symphony.
 
I have the AC on all the time, whether its hot or cold, top up or down. In the cold the AC stops the windscreen misting up, and when the weathers nice enough for the top to be down its nice having cool air blown at you.
 
Matmulder said:
Apparently AirCon increases petrol consumption by 10-20%.

Hence, I don't use mine. Besides, if I did, I'd need to have the windows wound up and I'm muffle that gorgeous Alfa V6 symphony.

Fixx0red. :)
 
paradigm said:
Meh, aircon on = better MPG than aircon off but windows open. This is down to extra drag.

No, what he said was wrong. He said it reduces petrol consumption. It doesn't, it reduces MPG ratings. It increases petrol consumption.

It was a correction of grammar.

EDIT: Oh hang on. Sorry,. I misread. Anyway, if you're doing 70MPH on a motorway, then yeah I guess AC is more fuel efficient than windows open.
 
Matmulder said:
Apparently AirCon reduces petrol consumption by 10-20%.

Hence, I don't use mine. Besides, if I did, I'd need to have the windows wound up and I'm muffle that gorgeous Alfa V6 symphony.

You should use it, or it'll break and end up costing you money to have it fixed. Wouldn't having your windows down also affect MPG?:p

edit-beaten.
 
paradigm said:
Meh, aircon on = better MPG than aircon off but windows open. This is down to extra drag.

Pretty sure someone did a test on this and this was only true when going over a certain speed (obviously!). Somewhere around 60mph iirc though it's hazy :p
 
Sunroof tilted now ive got a switch for it!

If im not going over 50 then windows down, over 50 windows up as the wind noise is annoying.
 
Wasn't it Jeremy Clarkson who was demonstrating that driving with your windows down costs you money (in increased consumption, due to drag) by throwing £10 notes out the window while he was driving??

I can't remember. Yes, its a good point that windows down increases drag...but, erm, I don't know enough about the facts to argue the toss ;)

But lets say at low speeds, windows down - at high speeds, AirCon :p
 
Matmulder said:
Wasn't it Jeremy Clarkson who was demonstrating that driving with your windows down costs you money (in increased consumption, due to drag) by throwing £10 notes out the window while he was driving??

I can't remember. Yes, its a good point that windows down increases drag...but, erm, I don't know enough about the facts to argue the toss ;)

But lets say at low speeds, windows down - at high speeds, AirCon :p
Basically... If you want to keep cool, you're gonna use more fuel.
 
Mythbusters did a feature on this.....

AC vs. Windows Down
Adam and Jamie tackle not so much a myth as what they call an "urban puzzle". The debate arises because both methods of cooling influence a car's fuel efficiency—air conditioning requires a lot of power to run, but at the same time, open windows create drag.

Revisited in MythBusters Revisited, Season 3, episode 38
Myth statement Status Notes
Running a car with air conditioning on is more fuel efficient than running with the windows down. Partly Busted Tests were performed under varying conditions (55 mph versus 45 mph). Also, the 55 mph test was using a computer to estimate fuel efficiency based on air intake, not actual fuel consumption, and showed A/C was more efficient. The 45 mph test consisted of running the tank until it was empty, and showed open windows were more efficient. This experiment--or one like it--is sometimes cited by the Magliozzi Brothers on Car Talk when presented with this question.
 
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In the Focus - AC if above 30mph. If not then windows down

In the Polo - Open that glorious sun roof as the place where the AC button should be is about 10 years too early!
 
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