I purchased a 165A alternator to take care of lights dimming, slow windows and just random voltage drops at idle. I noticed that the new alternator pulley has an outside diameter of about 2 3/8" while the old one has a diameter of a little over 3". Is this going to cause any issues with the rpms, ecu, etc.? Also, will I need a smaller belt?

I know about the big 3 but didn't when I bought the alternator so I still want to install it. I'm gonna do the big 3 first though.

I know 165A might be overkill since I don't have a system but the price was good and I will add a good system later on...

Any advice on this is greatly appreciated.

 

I would try it and see if you'll still have voltage drops and lights dimming once you get that 2 3/8" pulley ALT in. Only one way to find out.

 

Thanks. I think it will fix the voltage drops. I'm just concerned about the underdrive (or is it overdrive?) of the new pulley. I've read that it might affect the way the ECU handles the new higher voltages at low rpms.