Hi everybody,

i send a few question from Germany about the above-named overdrive Transmissions because my driveshaft was broken @4500rpm and destroy the case of the TH400,the floor pan,exhaust and and and.....$$$!

Now,iīm maybe plan to swap to a overdrive but not sure if itīs a big deal?

# everyone swap a TH200 or 700R4 in a 64-67 A-body?

# can i use the existing transmission cross member if i use the TH200R4,which parts i need ?

#i read about swap the Planet Gears from a TH400 to become the nearly the same effect?

The car is a 65 442 with 3,42 Gears and mild 455 so donīt want to race this car.


will be very happy about any information!

Best regards
Denis

ps.sorry for my English!

 

The 200 4R is the way to go. You just need to have it build to handle the torque of the 455. If you check out this posting at turbobuick.com it will shed some light on what should be done to make it bullit proof. http://www.turbobuick.com/forums/tra...ing-2004r.html

 

Thanks for the quick reply......and the site.
Why not the TH700,maybe easier to become here in Germ.


Not see the Transmission section in this forum,sorry.

 

Moved thread to transmission forum...

 

The 200-4R vs. 700R4 discussion comes up frequently on all automotive boards. Personally I prefer the 200-4R for the following reasons:

1. The 200-4R bolts to the Olds motor. The 700R4 requires an adapter plate.
2. The 200-4R has what most consider to be a better gear ratio split. The 700R4 has a lower first gear but then a cavernous drop between first and second.
3. The 200-4R is the same length as the TH400. The 700R4 is an oddball length. This is less of a problem for you, since you need a driveshaft anyway, but you can use a stock TH400 length driveshaft with the 200-4R. The 700R4 requires a custom shaft.
4. The 200-4R puts the crossmember in the same place as for the Jetaway or TH350. Those holes are already drilled in your frame rails. The 700R4 requires a unique crossmember location and new holes to be drilled.

Both transmissions require the small front yoke. The TH400 yoke won't work.

Both transmissions require beefing up to live behind an Olds motor. Parts are available for either. Neither will live long in stock form.

Both transmissions require routing a throttle valve cable and sourcing a bracket for the cable at the carb.

The 200-4R is very sensitive to heat, so an aux transmission cooler is a good idea.

 

One more point. I just noticed that you have a convertible. The crossmember bolts to tabs welded to the inside of the frame rails. Since you had a TH400 in a 65, you've apparently already modified these tabs. The 200-4R should allow the crossmember to bolt to the original location, if that wasn't cut off when the TH400 tabs were installed. The 700R4 requires new tabs to be welded on in either case.

 

Thanks Joe for you informative reply.....

do you know a good and cheap source,maybe i private person who ship to Germany....... i found this shop:

http://www.bowtieoverdrives.com/cata....php?ITEMID=11

but not sure if it will withstand the nearly stock 455/300HP

Regards
Denis

 

Good and cheap don't often fit together. I researched 2004R's for two years before I decided to buy from CK performance. I went with the full billet and my 455 hasn't broken it. My rear tires do feel the pain though.

 

I will second the endorsement of CK Performance. I've used them for 200-4R parts in the past. Very knowledgeable. Chris builds these transmissions to live behind 9 sec turbo Buicks.

 

Joe,can you write this :
The crossmember bolts to tabs welded to the inside of the frame rails. Since you had a TH400 in a 65, you've apparently already modified these tabs. The 200-4R should allow the crossmember to bolt to the original location, if that wasn't cut off when the TH400 tabs were installed

in other words please......because i donīt install the Th400 so i not sure what are "these tabs".

Maybe a pic will help.

regards
Denis

 

Denis,

On hardtops, the frame rails are simple "C" sections. The crossmember sits on the lower flange of the frame rail. In that case it's very easy to relocate the crossmember and drill new holes to bolt it in place.

Convertibles need extra frame stiffness to make up for not having a metal roof. The convertible frame is a full box section, which does not allow the crossmember to mount in the same way as on hardtops. Instead a separate tab is welded to the inside of the frame rail for the trans crossmember to bolt to. On the 1965 cars, the only available transmissions were the manual trans or the ST300, which are the same length, so these tabs are only designed to mount the crossmember in one location. The TH400 is longer and requires the crossmember to be mounted further back. On the convertibles the tabs don't go back that far, so someone must have welded additional metal in place to allow the crossmember to mount.

Just crawl under the car and look at where the crossmember bolts to the frame rails, and this will become obvious.

 

Maybe this helps a little......