I have the AEM pulleys on my car and wanted to know if they cause the car to have lower voltage than normal. A lot of people say that with a standard setup the voltage is close to 14.4 volts. Does the pulley affect the voltage?

 

Don't know, but I couldn't tell any difference in draw whan I had mine.

 

The UR Ultra SS crank pulley affects voltage. Do the AEM's underdrive at all? If so, I'm sure they decrease voltage.

 

I just spoke with AEM and it decrease the voltage. The pulley is about 30% larger which means the Alt is not spinning as fast. They did say unless you have a lot of power(which I do) the difference isnt too much while driving. I'm removing mine only because I'm pretty much done using mar car for racing.