...So...... no one running a regular 727 or 904 is using a lock up converter.
Unless there’s some current technology for those transmissions I’m not familiar with.
ugh???
Both transmissions got the factory lock-up functionality around '78 I think (give or take a year?).
As applicable to drag racing I would agree that most probably run non lock-up setups. However, I for one have a lock-up 518 here and would consider running a high-stall lock-up converter in it. I haven't gotten anywhere near actually being able to prep the transmission and make the appropriate changes to use that setup in my coupe, but one of these days I would consider doing so.