ok i had a question about the ac....how much mpg drop from it? does it drop more if it on max then if it was on norm?

 

Idk if its true or not, but Max is SUPPOSE to be more efficient, mainly because it is cooling and cycling the air inside the cab, and not cooling air from outside

 

A/C will drop your mpg 1-2 mpg at most. It's not a big deal.

 

in town maybe 1-2 mpg, on the highway i have noticed no change.

 

I have read that if you use it on the freeway it helps out your MPG because the widows are up creating less wind resistence, and it helps your motor to breath better. This was from MuscleMustangs&Fastfords.com. This could be bogus but....whatever.

Matthew

 

Nah, that's BS. The average A/C compressor takes 10-15 HP to run. The average car takes about 15 HP to keep a constant highway speed (70ish mph). Using the A/C, you're using more power to keep you moving and have the A/C on.

And your windows being up is so minor. Most cars are so aerodynamiacally challenged that there are other parts that will create wind resistance way before the windows will.

 

i read the same thing that matthew did.

soooo basically it makes no difference riding with the ac as opposed to the windows cracked?

 

Where did I say that? A/C will make mpg go down slightly.

 

yea it makes a difference maby in mpg but also at the pedal. go to a red light and take off with ur windows down, go ahead punch it. now next red light, windows up a.c on and punch it again. ur car will just chug along. it takes so much away from throttle response its not even funny. if my stang was older or i didnt have a gf i would probably rip the whole system out. it is usless except those certain days u leave it in the sun and u live in texas or florida lol

 

As said before, the power required to operate the a/c is more than the drag with the windows down. Living in Florida I've found the a/c is much better than having the windows down (I'm old and like to be comfortable...).

As far as the a/c using more HP when it is on high or low, the only real difference is the amount of electricity the blower motor is using. The a/c compressor doesn't increase in rpm when you switch from low to high. I doubt if you would even be able to feel the HP drop caused by the increased electrical load when the a/c is on high vs low.

Smitty