200-4R guys please help
Thread Starter
Racer
Joined: Apr 2006
Posts: 322
Likes: 0
From: Rockford MI
200-4R guys please help
Hey guys, Getting ready to do the 350 to 200 4R swap in my stock 78 L48. I have a 200 that I will be getting rebuilt very soon. Can you guys who have done this swap chime in and tell me what you did to complete the job?
Questions I have so far:
Does the original flex plate work for the swap?
What did you guys do for the Lockup wiring?
What did you guys do with the TV cable?
I plan to use the stock crossmember. Has anyone had problems doing this?
Will the front yoke on the driveshaft from the 350 work with the 200?
What did you guys do for adapting the cooling lines?
Was there any adapting that needed to be done with the shift cable?
I know there is alot of info on the bowtie overdrive site. I just wanted to hear directly from the guys that have done this.
If there are any questions that anyone can think of that I haven't asked please let me know.
Thank in advance
Questions I have so far:
Does the original flex plate work for the swap?
What did you guys do for the Lockup wiring?
What did you guys do with the TV cable?
I plan to use the stock crossmember. Has anyone had problems doing this?
Will the front yoke on the driveshaft from the 350 work with the 200?
What did you guys do for adapting the cooling lines?
Was there any adapting that needed to be done with the shift cable?
I know there is alot of info on the bowtie overdrive site. I just wanted to hear directly from the guys that have done this.
If there are any questions that anyone can think of that I haven't asked please let me know.
Thank in advance
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
Hey guys, Getting ready to do the 350 to 200 4R swap in my stock 78 L48. I have a 200 that I will be getting rebuilt very soon. Can you guys who have done this swap chime in and tell me what you did to complete the job?
Questions I have so far:
Does the original flex plate work for the swap?
It might, there are sometimes two converter hole patterns in the flexplate.....best to locate one that for sure will, and return it if necessary...
What did you guys do for the Lockup wiring?
On my '72 vert, the brake light sw. hot wire is orange, the white lights up the rear lights...so I used that to power a relay, that opens the contacts when energized...so then those contacts break open the SWITCHED HOT wire off say the yellow feeding the W/wipers.....there is a internal grounding switch that activates the lockup solenoid in at least 4th gear.....
What did you guys do with the TV cable?
you need make or obtain/maybe junkyard adaptation of the bracket to go to your carb...and make sure the position of that bracket is such that the cable has proper tension on it....VERY CRITICAL.....
I plan to use the stock crossmember. Has anyone had problems doing this?
being as you have a 350 the postion of the cross member maybe have to shift to the rear....depending honestly, I suspect it will not move, but there is a bracket on muncie cars that has to come off, as the tranny sets directly on the cross member.....best I can tell you...
Will the front yoke on the driveshaft from the 350 work with the 200?
YES.....
What did you guys do for adapting the cooling lines?
Screw them home, you maybe need a set of common hardware store brass adaptors...maybe a parts house...flare to just a NPT....maybe...
Was there any adapting that needed to be done with the shift cable?
Yes, maybe, the bracket going to the pan, bolt centers...one of them is typically in the right position, but the spacing is off for the other one....sometimes a piece of steel bar bolted over it...not hard to figger out....
I know there is alot of info on the bowtie overdrive site. I just wanted to hear directly from the guys that have done this.
If there are any questions that anyone can think of that I haven't asked please let me know.
Thank in advance
Questions I have so far:
Does the original flex plate work for the swap?
It might, there are sometimes two converter hole patterns in the flexplate.....best to locate one that for sure will, and return it if necessary...
What did you guys do for the Lockup wiring?
On my '72 vert, the brake light sw. hot wire is orange, the white lights up the rear lights...so I used that to power a relay, that opens the contacts when energized...so then those contacts break open the SWITCHED HOT wire off say the yellow feeding the W/wipers.....there is a internal grounding switch that activates the lockup solenoid in at least 4th gear.....
What did you guys do with the TV cable?
you need make or obtain/maybe junkyard adaptation of the bracket to go to your carb...and make sure the position of that bracket is such that the cable has proper tension on it....VERY CRITICAL.....
I plan to use the stock crossmember. Has anyone had problems doing this?
being as you have a 350 the postion of the cross member maybe have to shift to the rear....depending honestly, I suspect it will not move, but there is a bracket on muncie cars that has to come off, as the tranny sets directly on the cross member.....best I can tell you...
Will the front yoke on the driveshaft from the 350 work with the 200?
YES.....
What did you guys do for adapting the cooling lines?
Screw them home, you maybe need a set of common hardware store brass adaptors...maybe a parts house...flare to just a NPT....maybe...
Was there any adapting that needed to be done with the shift cable?
Yes, maybe, the bracket going to the pan, bolt centers...one of them is typically in the right position, but the spacing is off for the other one....sometimes a piece of steel bar bolted over it...not hard to figger out....
I know there is alot of info on the bowtie overdrive site. I just wanted to hear directly from the guys that have done this.
If there are any questions that anyone can think of that I haven't asked please let me know.
Thank in advance
Instructor
Joined: Sep 2008
Posts: 136
Likes: 0
From: Florence, Kentucky
I've rebuilt several years ago when I used to street and strip our Monte SS.
Recommendation. Go check out some Buick GN forum sites. There are a bunch of mods and depending what this came out of you might want to
even try to get a different valve body. Monte SS or Buick GN. Are you doing the buildup yourself? these are weak tranny's until they are built up.
As far as the lock up, if you put a manual switch on it and lock it up when rolling down the interstate, that's fine but there are a some kits
and different ways to do this as well.
Get an after market Torque converter and do yourself a favor. put a Tranny cooler on it if at all possible. I was pushing 420 ponies in a 355. These a good trannys but won't hold up unless you baby it or it's modded.
There are some governor mods that you can also do that will help.
the simple fix is to get a Buick GN governor to use. Problem is that GM
redesigned the governor and it's different and not as good as the original. (Controlling shift points)
depending on the vehicle this came out of, but may want to look at upgrading the pump. I can't remember but I think you want a 10 or 12 vein.. ?? you'll find them.
I will be building another Monte SS back up in the near future and I have to tell you that I'm going with a 700R. they're stronger trannys
and you can build them up too. Plus.. 1st gear is lower and 4th gear is higher.. A little more fun on both ends. ;-)
Lastly. someone mentioned the TP cable. It's very easy to adjust with the correct mounting. You can easily alter a bracket off of an 80's G body to fit the needs. But.. Do get it adjusted right. Engine off..
Hold throttle wide open, push the adjuster and then let off the throttle.
your done mounting plate is mounted correctly on the engine.
Good luck with the conversion.
Take Care
Don
Recommendation. Go check out some Buick GN forum sites. There are a bunch of mods and depending what this came out of you might want to
even try to get a different valve body. Monte SS or Buick GN. Are you doing the buildup yourself? these are weak tranny's until they are built up.
As far as the lock up, if you put a manual switch on it and lock it up when rolling down the interstate, that's fine but there are a some kits
and different ways to do this as well.
Get an after market Torque converter and do yourself a favor. put a Tranny cooler on it if at all possible. I was pushing 420 ponies in a 355. These a good trannys but won't hold up unless you baby it or it's modded.
There are some governor mods that you can also do that will help.
the simple fix is to get a Buick GN governor to use. Problem is that GM
redesigned the governor and it's different and not as good as the original. (Controlling shift points)
depending on the vehicle this came out of, but may want to look at upgrading the pump. I can't remember but I think you want a 10 or 12 vein.. ?? you'll find them.
I will be building another Monte SS back up in the near future and I have to tell you that I'm going with a 700R. they're stronger trannys
and you can build them up too. Plus.. 1st gear is lower and 4th gear is higher.. A little more fun on both ends. ;-)
Lastly. someone mentioned the TP cable. It's very easy to adjust with the correct mounting. You can easily alter a bracket off of an 80's G body to fit the needs. But.. Do get it adjusted right. Engine off..
Hold throttle wide open, push the adjuster and then let off the throttle.
your done mounting plate is mounted correctly on the engine.
Good luck with the conversion.
Take Care
Don
Burning Brakes
Joined: Nov 2006
Posts: 954
Likes: 40
2022 C3 of the Year Finalist - Modified
Try this link, you can calculate what you need.
http://www.2004r.com/speedoCalc/speedocalc.shtml
Avner
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Racer
Joined: Oct 2005
Posts: 457
Likes: 1
From: Royal Oak Michigan
I swapped my TH350 for a 200 4R- search my username I think I posted a lot of answers when I did mine.
I did this with my 80 - not sure how much is the same.
I did not have to modify my driveshaft length or yoke or get a new flex plate-it all bolted right in with the 2004R. I did buy the BTO cross member- but I think now I could have used my OEM one.
BTO makes a bracket to modify your shifter positions for your gear selector and at the trans.
BTO also sells conversion brackets for your Throttle cable hook up to the carb.
Darrel1
I did this with my 80 - not sure how much is the same.
I did not have to modify my driveshaft length or yoke or get a new flex plate-it all bolted right in with the 2004R. I did buy the BTO cross member- but I think now I could have used my OEM one.
BTO makes a bracket to modify your shifter positions for your gear selector and at the trans.
BTO also sells conversion brackets for your Throttle cable hook up to the carb.
Darrel1