KAVS Alternator Pulley
 

Looking at getting a 17% SC pulley, and while checking out KAVS Motorsport saw they had a 5% alternator pulley. Just curious what a different sized alternator pulley would accomplish exactly? From the description on their website it sounds like adding a reduced SC pulley makes the alternator and other things spin faster, is this correct? So adding the +5% alternator pulley will slow down the alternator back to normal speeds? Doesn't really make sense in my simple mind that the SC pulley would effect the speed of everything else? Smaller SC pulley I guess would equal smaller belt which just like a smaller gear goes faster to cover the same ground of a larger gear? So I guess what I'm getting at is the +5% alternator pulley for $50 a good add-on?
Thanks in advance!

You only need to change the size of the alternator pulley if you change the crank pulley...
Let's say you got a +2% crank pulley...this speeds up EVERTHING, including the ac, alternator, and sc...
If you ONLY change the sc pulley...EVERYTHING ELSE still runs at NORMAL SPEED CAUSE THEY ARE POWER TAKOFF PULLEIES....
most folks that get a +2 crank pulley never change the alternator pulley, no issues...the voltage might be slightly higher, but still "close enough" to be OK, and the ac is just cooler...

Save your money you don't need an alternator pulley. 99.9999% of cars with a supercharger pulley or larger crank pulley are using the stock alternator pulley. And there are no issues with. Just get a 17% pulley kit and enjoy it.
http://www.waymotorworks.com/wmw-pulley-package.html

Thanks to the both of you for the informational and speedy responses :) Decided to stay away from it and will probably be ordering today Way!