Okay, this is my 1st post on the new forum. I'm currently running a C-4 in my t-bird (2900 lbs 466 ci) running 6.40's and am running a used ATI converter, which ATI say is too lose for my combo. I am going to purchase a new converter and am thinking of switching to powerglide at the same time. I'm not crazy about a "GM :roll:" part on the car, but if it will help the car now, and later on down the road with more cubes, then I guess I can adjust. Just want some opinions on this from you guys, thanks.