A few questions from this newb. I am looking at purchasing a new transmission. I was heavily leaning towards a 700r4 until I started reading the threads here on the board. (what a nice resource!) It looks like the consensus here is that the 200-4r is the preferred tranny to swap into. Would a 200-4r hold up as well as a 700r4 with a 455 behind it? If so, which flex plate would you guys recommend? As always, I sincerely appreciate your tutelage and direction.
Well the 2004r is a good transmission when built right. There are a lot of people pushing 1000+ horsepower through them, but they are also rebuilding them after each racing season. If you are going to try a 2004r I would spend some money at the get go to get it built right with good strong parts, otherwise you will be spending more money getting it redone.
The flex-plate that works with a th350 will also work with the 2004R. The only slight advantage the 7004R has over the 2004R is that in stock form the 7004R can handle a bit more power. Once you get into the serious mods the 2004R is a better trans, but like Mark says above, it costs a pretty penny to have one done right.