First of all new here and thanks for any help that the great Buick faithful will send. I just purchased a 72 GS 350, yet buidling a 455 and wondering what is required to do a TH200 swap? If this has been discussed send me the thread, as a newbie please be patient. Thanks
Welcome from Montana! Sounds like a cool car. There's some threads down in the "juicebox" section for exactly what you're doing here: http://v8buick.com/index.php?forums/the-juice-box.11/ . Start a build thread in the "Member's Rides" area and you can ask questions as you go along, plus we all like to see what other guys are working on
Make sure it's built right - the 455 torque monster will eat up a stock-ish 200R. Several vendors have been recommended here - check it out. Also the Buick turbo board has lots of info on the 200.
If I'm remembering this correctly, there's a huge difference between a TH200 and a 200R4. The TH200 is junk and wouldn't last long behind a 3 cylinder Geo Metro. The 200R4 is what came in Buick Grand Nationals and can be built to be a sweet Trans with OD and a lock-up torque converter. The TH 200 has a square-ish pan with one corner lopped off and it says "Metric" as it was the first GM Trans to use all metric fasteners inside and out. The 200R4 has a pan that is shaped kinda like Montana and it isn't flat. Near the tail the pan is very shallow, just a bump bigger than the flange but the fluid/filter reservoir is pretty deep. You're probably talking about the 200R4 since the TH 200 is just a 3 speed with no overdrive.
the th200 takes lots of parts but can be built. alot of super stk run them since they are much lighter than a th400 and take less power to turn.
That was my thoughts on the original post, that he meant a TH200-4R since he mentioned OverDrive. I had a regular Th200 in my Cutlass Supreme. When I swapped from the wheezing 260 to a 350 Olds, I kept the trans out of cheapness. It lasted for the 2 years I owned it after that, but I most certainly was aware that it was more than likely a ticking time bomb and in general drove it as such.