I have had Holley 600's vac. sec., 750 vac. sec., Carter 625's (actual Max Wedge carbs), but now have a set of old Holley 660 Center squirters that have been reworked to like 690's. They are by far the best running set I have had on. More lower end response and the top end is unreal. They are on a Weiand tunnel ram that has only been port matched top to bottom and port matched to the heads. Also running just old cast iron heads.
Holley was blowing out the now-discontinued 660s for about $235 brand-new from their online store not long ago. I shouldn't have listened to the nay-sayers just bought a couple when I had the chance.
