670 vacuum secondary vs 650 double pumper

I used to recommend the 670 on this site, but I've seen issues with them posted across the net, so I'm reserving promoting them...at least for now.

With the 4spd and the gear you have, a 650/750 DP is a no brainer at this point :thumbrig:. Good luck if you decide to swap...I don't think you'll be disappointed.