200-4R Conversion

[strick9c10]

I was wondering if anyone has done this conversion...

I have a 79 C-10 that I purchased recently. It has a 425 horse 355 small block between the fenders , but still has the original Saginaw 3 speed transmission in it (the guy never got around to swapping it out).

I want to switch to an automatic, because Muncie & T-10 four speeds are just way too much $$$ in my neck of the woods. I was going to use a TH350 short shaft unit, so I can keep the same driveshaft, but am having a real hard time finding a decent 69-81 unit.

I know the 200-4R tranny is the same length, etc., as a short shaft TH350, but will a 200-4R fit without modifications to the cab, floors, cross-member, etc.

Any ideas, thoughts, etc., are most appreciated & welcome!

[bigblock73]

It'll clear the body just fine, but you might have to slide the crossmember forward/backward slightly for it to bolt up.

200's are GREAT transmissions, CAr Craft had an article on them in their recent issue, featuring Art Carr...who is an OD expert.

[strick9c10]

Thanks for the info. I read that article... that's what got me to thinking about using one. From what I've read, the 200-4R's have a lot more going for them than the more common 700 OD units.

Anyone have any more input re: the cross-member and other small details, like transmission lines, tv cables, detent cables, modulators & lines, and solenoids.

I'm old school... thanks for your info & patience!

[morcey2]

I put a junk-yard 200-4R in a 73 Buick Century years ago and it was mostly trivial. I drove that sucker for another 40000 miles after the swap. A big boat getting 20+mpg! It was great!

You'll need to add a TV cable connector on your carb and setup the TV cable correctly, otherwise the new tranny will be very short for this world. You'll probably need to either switch to a radiator w/ an integral tranny cooler or run an aux cooler in front of the radiator. If you can get cooler lines and radiator from a truck w/ a 350 tranny, they should work for the 200-4R. On my swap, the cooler lines had to be bent very slightly to fit the new tranny.

If you're not getting a rebuilt unit, do yourself a favor and get a hardened stator support and have the pump rebuilt w/ a 10-vane pump w/ hardened vanes. The stock stator support isn't hardened and wears quite dramatically. If you are getting a rebuilt unit, make sure it has some basic upgrades. I'll find an article on it and post a link when I have a minute.

The crossmember/transmission mount is where I'm a little in the dark w/ trucks. The buick was easy because it came originally w/ a 350 and had a 400 as a option. I just kept the 350 mount and pushed the crossmember back to the 400 frame holes. I think that the trucks usually came w/ a short tailshaft 400 and used the same crossmember for the 350 so a 350 mount on the crossmember mounted in the 400 holes should work. Again, that's where I'm a little short on experience.

I love the 200-4R. I'm getting one out of an 86 regal (non-turbo unfortunately) and building it for 400+ hp sometime in the next little while. Then I'll have to find something to put it in.

Matt

[strick9c10]

One of the reasons why I purchased this truck is because many performance mods were already done. The truck already has a brand new Griffin radiator where you can plumb tranny lines into it... no need to swap.

Will pre-bent tranny lines (like from LMC) that would be for a TH350 work for the 200-4R? According to the research I've done, the 200-4R is of the same dimensions as a short shaft TH350. I've also read that you can use the same transmission mount and driveshaft. So I'm going to assume I won't have to modify or change the cross-member.

Lastly, sorry for the ignorance, but I'm going to assume that the tv cable replaces the "old" transmission modulator line.

Any other ideas, tips... let 'em rip!

[Jonboy]

Yes on both accounts. The trans cooler lines will work fine. The TV will replace both the modulator line and kick down cable.

You may have to move the crossmember back a little, but you can use the same crossmember and mount.

[nekkidhillbilly]

there 9 sec buicks running them

there the same length at a th350

find one from a turbo buick monte ss hurst olds or gp 2+2 if possible there stronger

[lurch115]

ummm...i recall doing this same swap several years ago and had to move the tranny cross member back like 7 inches....

[strick9c10]

Thanks for the info! Some of the answers I was looking for just aren't out on the internet or in truck magazines. I did find two stories that give good info on how strong the 200-4R can be with some minor updates, as well as swapping one in a 1968 C-10.

Here are the links:

http://www.sporttruck.com/techarticl...ion/index.html

http://www.carcraft.com/techarticles...ild/index.html

In regards to the last two posts... from what I've read, GM as well as BOP used the same transmission in a number of different applications. In other words, the same transmission that was in a Buick GN was also in Grandma's grocery-getter Malibu. "Stronger" units were not limited only to the higher performance models.

Also, in moving the cross-member back 7 inches or so, are you sure this wasn't for a 700-4R unit? They are quite a bit longer in length. That's why I'm not using that particular unit.

Thanks again for everyone's input, opinion & help!

[morcey2]

A couple more links for you:

http://www.maliburacing.com/transmission_swaps.html

http://www.442.com/oldsfaq/oft200.htm

The 350/powerglide/muncie-3-speed mount is 20 3/8" back from the front of the bellhousing. The 200-4R is 27" back. The 400 is 26 15/16" back, so close enough for a 200-4R. That's why the crossmember needs to move back about 7".

Keep us posted.

Matt

[nekkidhillbilly]

Originally Posted by lurch115

ummm...i recall doing this same swap several years ago and had to move the tranny cross member back like 7 inches....

um for what there the same length as a th350

[nekkidhillbilly]

Originally Posted by morcey2

A couple more links for you:

http://www.maliburacing.com/transmission_swaps.html

http://www.442.com/oldsfaq/oft200.htm

The 350/powerglide/muncie-3-speed mount is 20 3/8" back from the front of the bellhousing. The 200-4R is 27" back. The 400 is 26 15/16" back, so close enough for a 200-4R. That's why the crossmember needs to move back about 7".

Keep us posted.

Matt

y is it so far up on the trucks on a gm a body car with a th350 they will bolt right in place

[nekkidhillbilly]

http://www.ckperformance.com/

http://www.turbobuick.com/

also the 200-4r brf code is the hp model and yes it was only offered in the upscale performance cars. not the grocery getters. i have one in my garage going into my gran sport.

[nekkidhillbilly]

you want a brf, kz ,cz trans there all the hp models there shift points differ but are the same in strength

[strick9c10]

Thanks for all the help & info! I'll be on the look-out for those particular RPO codes nekkidhillbilly mentioned... although everywhere I've read from factory GM manuals, to books on rebuilding transmissions, and in many different magazines, it never mentions these particular units. Weird.

I guess moving the cross-member back is part of the game. To quote Sport Truck Magazine... "The 200-4R is the same length and uses the same yoke, gearshift, and cooler lines as a Powerglide or TH350. In fact, in a swap situation, all you have to do is move the trans crossmember, depending on what tailshaft you have."

Of course, it never says WHY you have to! But from the info listed here as well as from others I've talked to, it's because the mount is farther back. Same length, same mount, just a farther back connecting point.

Any other tips or info from anyone who has actually done this swap would be cool. Pictures would be really cool!

[jdurant]

They are different in the different models. They have different valve bodies and servos. The turbo Buicks and Monte Carlo SSs are a little better, but they should be all about the same strength. I thought the ss was labeled either cz or cq, depending on year. The buicks are labeled brf, bq. If the label is torn off of the tailshaft, then they should be labeled on the valve body or have a pink mark. If you do plan to rebuild, I know a guy who will truely truely do you right, but he is down here in Houston.

[OrangeAnimal]

I got a 200R4 from transmissioncenter.net for a 80 Elcamino check them out. I got a different crossmember to replace the factory one and it was moved back a bit. It was really not a big deal to move it and the driveshaft went right into it.

[nekkidhillbilly]

Originally Posted by jdurant

They are different in the different models. They have different valve bodies and servos. The turbo Buicks and Monte Carlo SSs are a little better, but they should be all about the same strength. I thought the ss was labeled either cz or cq, depending on year. The buicks are labeled brf, bq. If the label is torn off of the tailshaft, then they should be labeled on the valve body or have a pink mark. If you do plan to rebuild, I know a guy who will truely truely do you right, but he is down here in Houston.

there was a kz and cz they both where offered in ss i have kz at home the only main difference is the shift point setting in the valve bodies in hi po ones

[SS68]

whos the guy here down in houston? im about to pick one up this weekend here in dallas dont really know who to trust with a rebuild most those guys look like crooks

[nekkidhillbilly]

search on turbobuick and see they are the 200-4r gods

[joe231]

bowtieoverdrives.com

[jdurant]

He's a good friend. His name is J.D. He's been building them on the side for a few years now and some have gone into really fast cars (one being his often daily driven high ten second 3500lb car). He's alot cheaper than anybody else and he will build it the way you want it. He's taken apart alot of trannys built by others. There have been a couple of instances where parts that people pay for aren't even there. It is hard to find somebody to trust.
Here are a couple of other guys known to build 200s.
century, pts, and ck performance
Century is also in the Houston area. Call around and get some prices from these guys.
I think you'll pay alot less and get more and sooner if you use J.D. I'll pm you his email address. I wouldn't let anybody else build one for me.