Can anyone add some information as to which would be better?

The cost of such a change leans me towards the the upper for a quick 2-4 lbs of boost...except for the pain of pulling the eaton upper pulley. Moreover, the lowers are quite pricey and are they worth the increased cost??
I'm looking to increase some hp, while still using the truck as a daily driver... I hate knowing that a few Vette's and Lightning's out there have more HP than me! Call it HP envy....
Any comments would be helpful!
Thanks,
Brian

 

One of the differences that I took into consideration was when going with a smaller upper, you end up running into belt slippage; you are reducing the contact area of the belt.

 

Go w/ the lower pulley swap... a smaller upper will cause blet slippage and you need special tools to remove the pulley from the blower snout or you will mess it up and your s/c will be crap...

Dave