[GeorgeWashingtonsGhost]

I never fight here at FR, but I'm ready to go down swinging on this one.. No one can tell me that heavy A/C use does not shorten an engine's survival. Horsepower is degraded when A/C is on because A/C is a 'drag' on the engine. An engine has to work harder when A/C is on, versus when it's not in use. TRY IT YOURSELF, from a dead stop with A/C on, versus A/C off. You can't tell me that A/C isn't a drag on an engine. I'll get back to you when I hit the 300,000 mile mark on my 1.8T engine. I DO use A/C, but very very sparingly.. /snicker spit.

Don't EVER race with your A/C on! You might as well throw your white hanky out the window! You here at FR are all my brothers, but go ahead.. Try and 'dog house' me on this one.

[nascarnation]

It’s all a matter of degree. These days most engines run 200,000 miles plus and I’d bet most of the ones in the sunbelt and the southwest have the A/C on all the time six months of the year.

Is there any evidence engines in Florida, Alabama, and Mississippi fail quicker than the ones in Maine and Vermont?

[steve86]

No one can tell me that heavy A/C use does not shorten an engine's survival.

What, by 30 miles out of 300,000? (on an otherwise well-cared for powerplant).

Horsepower is degraded when A/C is on because A/C is a 'drag' on the engine.

Yes, the compressor use 5-6 hp peak on a small 4, which I have.

TRY IT YOURSELF, from a dead stop with A/C on, versus A/C off.

Yes, I can feel the difference in acceleration on this four cylinder vehicle. But very little. A passenger would have a hard time detecting the difference if they couldn't see me hitting the switch.

Don't EVER race with your A/C on!

On most vehicles a solenoid or switch disables the compressor at full throttle, for passing, etc.

Don't take it so personally and have a great weekend!

[CodeToad]

I have a 400hp engine and 1.3hp compressor. Don’t think I’d notice it much.