need a stall speed for a 904 trans.. 72 demon with a 408 stroker, 529 torque and 472 hp, run on street/strip. 3.73 rear gear for now but going to 3.23 soon.. 265/60/15 tires
i'd call all three of the popular ones.. dynamic,ptc and ultimate and see what they recommend..
the biggest thing when talking with them is to be 100% honest on intended use.. and also have as much information as possible about your combo.. if not 100% honest about the intended use or the combo you will not be happy with the converter..