Power loss when the AC is on
08-28-2012, 12:51 PM
#2
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Join Date: 08-06-2008
Location: Grand Haven, MI
Posts: 1,761
Yes, you do rob HP from the engine with the AC on. I can feel my compressor come on, with the AC and Defroster, but 15 - 20 HP seems excesive.
I am sure someone on the board can tell us exactly how much power they take....
I am sure someone on the board can tell us exactly how much power they take....
08-28-2012, 12:59 PM
#3
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Join Date: 06-22-2010
Location: Wisconsin
Posts: 387
15-20hp was only a guess but I can feel it's not as peppy.
08-28-2012, 03:04 PM
#4
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Join Date: 08-03-2009
Location: D.C., Md., Va. area
Posts: 837
This is what happens with a turbo 4, as opposed to a V8. My SS has 5 more hp and close to the same in torque than my Avalanche, but those extra 4 cylinders make a huge difference with how much torque there is and when you feel it.
08-28-2012, 03:55 PM
#6
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Join Date: 07-05-2008
Location: Akron Ohio
Posts: 5,464
I can feel it in my V6 and V8 too.
But on the other hand my Fiero V6 is faster by a couple tenths in the quarter mile with the AC on.
Most cars compensate for this with added fuel but there is still a little feel in all of them even the V8. Drag on the engine is drag no matter the cylinders or HP.
But on the other hand my Fiero V6 is faster by a couple tenths in the quarter mile with the AC on.
Most cars compensate for this with added fuel but there is still a little feel in all of them even the V8. Drag on the engine is drag no matter the cylinders or HP.
08-28-2012, 05:26 PM
#8
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Join Date: 08-06-2008
Location: Grand Haven, MI
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I was curious so I did a little digging and found a few discussions about this. One said that the AC compressor takes between 10 -12 HP to run, and the other one said that modern cars use about 5 HP, but neither were from an auto or compressor manufacture....
With our 4 bangers, you definatly feel it when it's on, so as others have said, "no worries"
With our 4 bangers, you definatly feel it when it's on, so as others have said, "no worries"
08-28-2012, 06:29 PM
#9
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Location: Sarasota, FL
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08-28-2012, 07:27 PM
#10
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Join Date: 05-09-2006
Location: "Upland" Mesa, Arizona
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Generally motorheads will say 8-10 HP. But frankly every vehicle and matching a/c system is different. The auto industry statement is usually 5-8%...again depending on vehicle and system (at least that's what GM Engineering once stated).
Some years ago, it was 10-15%. But technologies have improved.
Oh, and on my use of the ac unit....as some have stated, almost all the time because of the climate......even sometimes with the sun roof open.
Also I think you'll find that the use of the ac is more noticeable when in traffic and stop and go. It's the heat build up under the hood. Once you clean out the hotter air, like using the Interstate, it is less noticeable.
Some years ago, it was 10-15%. But technologies have improved.
Oh, and on my use of the ac unit....as some have stated, almost all the time because of the climate......even sometimes with the sun roof open.
Also I think you'll find that the use of the ac is more noticeable when in traffic and stop and go. It's the heat build up under the hood. Once you clean out the hotter air, like using the Interstate, it is less noticeable.