Depends some will say it works great with a stock D5 or a 12" 2800 stall and some will say you will need a 9" 3000-3200 stall converter.... If it were me I'd get the 9" 3000-3200 stall converter, but that's just me and I have a TE-44 with a 12" 2800 stall converter....
HTH
I have a 51. It actually felt alright with the stock D5. I'm running a Vigilante now. The car runs alittle hotter. I'll be putting the stock or orange strip back in soon. Need a single disc LU Vigilante?
I have installed several PT51 for customers. One guy was using a mod. D5 converter and it had some lag. Purchased a JW 10" NL converter and loves it. I stick with the TE 44's myself.