Rob_Mopar wrote:
The 350/350 combo is the ubiquitous swap combo. Even I've done it. A TH350 is pretty tough, and pretty simple. If you are planning on highway gears in the back and 350-ish horse it's stone ax reliable and will cruise all day long. If you are planning to run anything numerically higher than say 3.42's you'll want overdrive. Hey, it's a Jag after all.
Unless you are planning for something really stout in front of this transmission a TH400 is overkill. I have been in a TH400 equipped LeMans that accidentally got shifted into reverse at highway speeds. The car tried changing directions. Trans never complained. The rest of the car did...
The TH200 Metric trans is an abomination. I doubt there are many left on the road. The 200R4 was much better and has OD.
I don't like the gear spread on the 700R4. First is very steep and a big drop to 2nd. It's a truck trans that got put in cars. If I were going to play with a GM cruiser I'd build up a 200R4 with aftermarket parts.
As I was reading through this thread (no offense to anyone) I was discouraged at the misinformation. As someone who manages three transmission shops and is a certified GM freak, I think Rob Mopar hit the nail on the head.
THM200C - don't waste your time. gut it and use it as a dinner bell.
THM200-4r - Same basic design as the 200 with OD. Vastly better than the 200. Nearly perfect gear spreads. If you have the money, it can be built stronger than the 700r4 despite its smaller size. The 200-4r was used in Grand Nationals from the factory, and I personally know many guys who are putting 600+ hp to the ground with a 200-4r. Its weakness is overall diameter. Its stronger than it looks, and fine for a heavy car/modest torque, but not wise for something like a 3/4 ton pickup that tows 8000 lbs.
TH350/TH350C - The "C" indicates lockup converter which started in about 1982. I personally prefer the non-lockup since the lockup circuit is an added complexity that sometimes fails. When it does, the converter doesn't unlock. Strong if built well, but only three speeds
TH400 - The biggun. Great for HD trucks, bullet proof in cars. Never available with a lock up converter. Good gear ratio spreads. Simple design that works great.
TH700R4 - A derivative of the TH350C, but many differences. The first gear ratio is 3.06 and second is 1.62. That is the largest ratio spread of any automatic transmission ever produced. Unless your torque curve looks like Kansas, its not my favorite. Plenty strong if built right. I recommend replacing the input drum with a billet unit for anything over 350 lb-ft of input torque.
4L80-E - There was never a non "E" 4L80, so it will require either a manual valvebody or a standalone controller. This is in many ways the TH400 with OD. Beefy. Nice. Overkill.
4L60/4L60E - 4L60 is simply another way to describe a 700R4. The 4L60E is simply a 700R4 that is electronically controlled.
On a side note - Most of the 200s were cast in either chevy OR BOP. Most of the 200-4Rs were cast with a universal bellhousing (usually called fit-all). TH350s and TH400s were cast in chevy or BOP. 700r4s were rumored to have had a few cast with the BOP pattern, but of the few thousand I've seen, none were BOP. All 4L60E and 4L80E are chevy pattern only.