At some point when it is necessary, I may replace the 904 in my 81 Imperial with a 500 OD from like an early 90s Dakota. The thinking being they can be acquired fairly easily and cheaply and offer the option of installed a better ratio ring and pinion in the rear instead of the economy 2.21 that is in there now. The cats have been removed from the car and the smog is freewheeling which has made a noticeable if not gigantic difference. Maybe put in a 2.94 or 3.23. The OD would basically...
Replacing 904 with 500 Trans
