[Karl Bebout]

I know its not a C4 but for years I ran a TH400, with a 3200 stall converter, behind my healthy RAT motor and liked it a lot. I've always been a bug about cooling the tranny so I ran a Derale tranny pan, with the cooling tubes, as well as at least a 12"x12" cooler and even in Southern AZ, never had tranny troubles. I've since gone with a manual 4L80 and really like that 4th gear overdrive. Makes 85MPH cruising at 3000RPM much nicer than the 4000RPM I used to have. I use the same cooling set up and still do not have any tranny overheating issues. I'd strongly suggest getting some tranny with the OD final ratio. More money up front, but, to me, well worth it, as is the overkill on the cooling.