Mythbusters, that monument of scientific methods.
I always found that at highway speeds, my cars got equal or better MPG with AC on/windows up then AC off/windows down. We tried it on a trip in my Civic back in the day. If you want to say the additional weight costs some MPG, sure, but it is pretty negligible. I would speculate AC diminishes MPG around town, but again, there are so many variables, so what? Laying off the skinny pedal on the right is a far bigger influence to local MPG. The argument is weak on both sides and therefore the MPG argument is moot.
I think we all agree the HP impact is also negligible, especially with more modern compressors, which I am pretty sure are more efficient then old C6 compressors.
And on cool high humidity days, AC does make defrosters work better. There is no doubt about that. The AC died in my Olds late last summer. There are some days, especially cooler rainy days, that the windows all fog up (not just the windshield) and the best I can hope for is a mostly clear windshield. The condition grows worse with more people in the car due to the extra body heat. There is a reason why modern cars turn the AC on when you hit the defrost button.
I know it hurt the resale on my 82 Trans Am. A lot of people called, heard no AC and said ‘no thanks’. T-Tops, PW and all.
Justin is right – clutter or weight savings for real race cars. I like my DD AC, I hate going a lot of places (like work) all sweaty. I better get it fixed.
Besides, pulling the AC is just a redneck hack.
