I have seen OBX alternator and water pump pulleys floating around ebay if anyone has them are they the same size as stock just weigh less and still use oem belt? I have mossy performance light weight crank pulley.

 

Well generally the water pump doesent change size, but some companys use smaller alt pulleys for more power to accessories, and some use bigger alt pulleys for less spin, which ultimately frees a tiny bit of power from the crank.

It should say either "underdrive" or "overdrive". That will tell you if its bigger or smaller thab oem. If it doesnt say those, then its oem size, just lighter.

And as far as obx goes, their not bad. Ive used some of their stuff, nothing major though. Definitely better than a lot of other cheap brands