What's the best "bang for the buck" Underdrive Pully to get for my car?

 

Also, i've been reading that getting a Different pulley will take away from other things such as AC and that sort of thing, is it a big difference in what it takes away from to give you more HP?

 

I think Motoblue or ASP are the best pulleys to get.

As for taking away A/C and other things, its too little to notice.

 

^^ He's right!! ASP is the best that I've heard of with Motoblue in Second. Unless you are running a big sound system you should be fine and not even notice. I believe that if you are running a big sound system you'll need a capacitor to offset the power loss.