The torqueflight is a very forgiving trans. My problem has been as you expect more from them the more “tricks of the trade” there are to make all the parts dance in harmony. The 727 I used to run was seemingly happy behind our W5 mill, but when the W8 came into play, and with data acquisition, we started experiencing part failures and noted shift time (rpm it took for shift) that probably wouldn’t even be noted with many street/strip combos. I ended up taking the unit to Pro Trans and they corrected some issues with it, including its tendency to throw front clutch pack springs (still a mystery). The 904 in my car was built in the mid/late 90’s by a good builder out of Minneapolis for my dads then 400hp combo. Again attention to detail perhaps is the reason it’s surviving low 9 sec passes (I know if you went to him and said “here’s what I’m going to do….” This would NOT be the unit he’d build). I’ve had it apart and there’s some nice machine work. Drums drilled for fluid evacuation. An extra shim behind the pump. Spacers on the apply pistons. Stuff I’m sure that somehow makes everything work “in time”.

I just hope the guy at the present shop can figure this out….. that wagon needs to run!