Are under drive pully's easy to install?
Is it worth the buck?
What kinda hp are we looking at?

 

on the d16a6's i believe aem claims 5-8hp. 8 being a modded engine. My buddy says he could really feel a difference, well more so than his I/H/E

 

oh and for the buck......the crank takes care of the majority of that expected hp number, so if you were looking for bang for the buck i would go with that one only. as far as the install is concerned be ready to tackle that crank bolt with at least a 700ft-lb inpact wrench, although some people are lucky and can get the bolt off with no hastles. there has also been some debate as to whether or not the aftermarket pulley provides the "ballancing" that the stocker does.