Should Ryan really be bypassing his car's air conditioner compressor to get more performance?

Dear Car Talk

Dear Car Talk | Mar 01, 2007

Dear Tom and Ray:



I am an 18-year-old guy, so naturally I am trying to get as much performance out of my car as possible. I recently developed the bright idea of bypassing the air conditioner's compressor with a shorter belt -- just for the winter (I couldn't do without AC in the summer). I thought it would give me a little more power. Now, my old man says that if the compressor isn't turning, it might cause problems when I hook it back up again. Is this true, or is he just afraid that more power means more speeding tickets? -- Ryan

RAY: Both, Ryan. If it's an old compressor and you let it sit idle all winter, you take several risks. First, the seals and gaskets can dry out and crack because they won't get lubricated.

TOM: And worse, the whole unit could simply seize up due to lack of use. So we don't advise this route.

RAY: Plus, you won't increase your power. On every modern car, the engine-management computer automatically shuts off the air conditioner when you call for maximum power from the engine. If you were to step on the gas to accelerate onto a highway, for example, the air conditioner would automatically be cut off during that acceleration anyway. So you're not gaining anything.

TOM: And you DO need the air conditioner in the winter. It's not there just to cool the cabin. It also removes moisture from the cabin air, and it's crucial in defogging your windshield. So in addition to not gaining any power, you won't be able to see, either.

RAY: It's not speeding tickets your father is worried about, Ryan, it's hospital bills. Listen to the man.

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