Beefing Up 904

Depends on what you are going to do with it, and how powerful the engine is. If it is fairly stock engine, for the street, I would recommend a manual valve body, deep trans pan and increase the high gear clutches and change the spring in the drum , rebuild with good parts. The AMX I drive has a Torque Command transmission, AMC's version of a 904. It has gone 9.90s in the 1/4 mile at 3200 lbs. Before last freshening, had over 300 runs. The last 904 I built, I had over $1000 in parts, and already had the low gear set, valve body and deep pan.