Let me see if I can help. I have 5.9 Magnum, KB .04 over pistons. Air gap intake, Hughes roller cam, Indy x heads. Headers, MSD ignition. I am currently running a 625 Carter that works pretty good but bogs. Tried an Eddy 750 and it killed the engine. I think the 625 Street demon sounds good for my set up and the ops. I think I'd like a 670 Street Avenger. Had a 770 on a 383 that worked perfectly.

‘72 Charger, 5.9 Magnum, Tremec 5 spd., Pro-Touring
‘14 Big Horn, Quad Cab, 4x4, 1500