You can also remove the a/c compressor and install a bypass pulley in its place. You can still use the standard belt this way, just run it to the bypass pulley instead of the a/c compressor. RockAuto has them at the link. http://www.rockauto.com/en/catalog/chevrolet,2001,impala,3.8l+v6,1384084,heat+&+air+conditioning,a/c+compressor+bypass+pulley,10329
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You can also remove the a/c compressor and install a bypass pulley in its place. You can still use the standard belt this way, just run it to the bypass pulley instead of the a/c compressor. RockAuto has them at the link.
http://www.rockauto.com/en/catalog/chevrolet,2001,impala,3.8l+v6,1384084,heat+&+air+conditioning,a/c+compressor+bypass+pulley,10329