I know that underdriven pulleys aren't good with bigger car audio systems, but what is considered the cutoff point where you should not use one? Also, exactly what would be affected if a larger car audio system was used in combination with an underdrive pulley? I've always found this vague as no one has elaborated on this subject. Thanks in advance!

 

I am running a good size system and never had any problems. I actually had a MUCH bigger set up in my Xterra (2) JL 1000/1 and (2) 300/2 amps, which I also had UR underdrive pulleys.

Where do you get this information you speak of?

 

It depends on the vehicle, and the alternator really. I never recomend it, however I am coming from a honda background where using underdrive pulleys with a high current draw system didn't work well together. You can use a high end stereo with the pulleys, but it's when you start getting into an SPL style setup with amps that have a very high current or amp draw that you want to stay away from using underdrive pulleys. In some cases, these types of setups will require you to modify or change out your alternaotr NE way to help keep up with the power supply. IF you don't have a high current or amp draw you should have no trouble using underdrive pulleys.... But it's always safe not to in that situation