200R4 swap into 71 Skylark 350.

Discussion in 'The Bench' started by BrianinStLouis, Jul 6, 2014.

  1. BrianinStLouis

    BrianinStLouis Silver Level contributor

    Hi all,
    Since an engine rebuild is in the near future due to low oil pressure, ticking and now, yet another leaking water pump. I am thinking about a OD transmission for my 71 350 Skylark. My original 350 turbo has 115xxx miles and makes all sort of funny noises. I may as well do the upgrade at the same time as the engine rebuild.

    Would the 200r4 be a good choice?

    What all would be required? Torque converter? Kickdown? Trans mount? Speedometer? Adapter needed? Car is column shift with a Q-Jet.

    I'm open to suggestions and especially advice.

    Thanks in advance!

    Brian (in St Louis)
  2. Deacon07

    Deacon07 1969 Buick Skylark

    This thread got me started. I also used the kick down location on the gas pedal to hook up the TV cable. You may need spacers to bolt the tc to the flexplate.


    Ckperformance and extreme automatics are highly recommended. You'll also need a 200 cover. But that's not a big deal.
  3. BrianinStLouis

    BrianinStLouis Silver Level contributor

    Thanks Deacon..I've just begun reading this thread and it's just what I was looking for.
  4. DauntlessSB92

    DauntlessSB92 Addicted to Buick

    If you do a search you will get all the information you need here on the forums. But if you are replacing a th350 you can keep your driveshaft. You simply have to move the cross member back to the th400 location which is already drilled from the factory. Speedo will work, shifter will work (in some cases the neutral safety switch may need modification but I have been driving with a swap for 4 years with no issue. Just readjust shift linkage after install. ) you will need to find a TV cable and you will need a TV arm on the carb. Some companies sell kits to do this like TV made easy. But the best way to do it is send your carb to Ken at Everyday performance as he does the conversions. Being that you are considering an engine rebuild having the carb rebuilt sounds like a good idea.
  5. Mark Demko

    Mark Demko Well-Known Member

    If you are going to put a 2004r trans in, you "should" change the rear gears. You probably have a mid 2 series gear in there now if its stock, with the trans in overdrive the engine rpm will be super low in overdrive at freeway speeds, unless you going to drive 100 mph. I would Change to at least a 3.42 gear
  6. BrianinStLouis

    BrianinStLouis Silver Level contributor

    Hmm, seems like this may be cost prohibitive for now.
  7. Mark Demko

    Mark Demko Well-Known Member

    Honestly, I would leave the 350 trans in it (get it rebuilt)
    Unfortunatley with an overdrive swap, its more than the trans. as your finding out. The main reason people use an overdrive is to be able to cruise on the highway IF you have deeper gears in the rear, which if the gears in your diff. are original (probably 2.56/2.73) you wont reap the benefits of an overdrive trans.
  8. BrianinStLouis

    BrianinStLouis Silver Level contributor

    I've already called a transmission shop to rebuild the stock 350. He quoted me $800.

    The machine shop is going to give me a quote to rebuild the engine as well as the transmission.
  9. rmstg2

    rmstg2 Gold Level Contributor

    Is that just for the rebuild or is he going to do the R & R? $800.00 is a little steep if you are going to pull it.

    Bob H.
  10. BrianinStLouis

    BrianinStLouis Silver Level contributor

    Nope, that is with me doing the R and R. I agree....I was a little stunned when he said 800.

    Another trans shop quoted me 500 if I do the R and R. Thats more inline with what i expected.

    I'm still waiting for a quote from the machine shop.

    Wish me luck!
  11. TXGS

    TXGS Paint by numbers 70 GS 455 4spd

    I would suggest you look around. $800 seems pricey for a turbo 350 build.

    I run a 200 4r behind my 350 I changed the rear gear set and convertor everything fit like a glove. I will say that the drive shaft pushes into the transmission a bit more than I would like considering the bounce and jounce of the rearend. I have considered taking an inch or so out of the driveshaft to limit the pressure put on the back of the tail shaft. Just my experiences.
  12. Electra-fied

    Electra-fied GR8WHTE

    Unfortunately, 800-900 is going rate for rebuilds these days. I couldn't find anything less that 825 for my th400...so I settled for a used th400 from a car with 80,000miles. This price range required me to R and R the tranny myself. Gone are the days, such is life.
  13. TXGS

    TXGS Paint by numbers 70 GS 455 4spd

    I assume prices vary. But you may be right the last 350 I did was in 2006. The cost then for me was $550 no R&R.
  14. John Codman

    John Codman Platinum Level Contributor

    Glad to see that you are sticking with the THM 350. Remember that all 350s are not created equal. Some have bigger clutch packs then others. You want the maximum number of steels and friction discs possible. The "Metric 200" is a good light-duty box. I would not use one in even a medium-duty application. GM tried this and they spend many dollars replacing or repairing the 200s on warranty. The 200 works great behind a stock 3.8 V6 in a mid-size car.
  15. TXGS

    TXGS Paint by numbers 70 GS 455 4spd

    Was it the adjustable bands on the Metric 200?
  16. BrianinStLouis

    BrianinStLouis Silver Level contributor

    The machine shop that is going to rebuild the 350 engine quoted me 700 for rebuilding the trans. I'll have to do the R&R.
    I just going to let this shop do it all.
  17. staged70

    staged70 RIP

    Brian where did you check for the trans rebuild. The parts are like 125 for the rebuild so I can check around for you if you like.
  18. Premier 350

    Premier 350 Chris (aka Webby)

    I guess it depends on how much use the car gets too. Your USA petrol prices are lower than Australias, but how long would it take to for the fuel savings to pay the extra for an overdrive?

    I'm ignoring the less wear on the engine factor, and also the performance advantages of having the best of both worlds- short gears for acceleration & the overdrive for cruising.

    I'd like to do the conversion to my 'lark, but considering the use it gets it would take years to pay for it all.

    And here in Aus, Buick pattern TH700 are plentyful. Hundreds of thousands of Holden Commodores came with 'em. And the 3800 V6.

    Not trying to talk you out of it, Brian, just my ramblings............

    And your TH 350 rebuild prices are way lower than ours, I was quoted a ballpark figure of $1200 AUD. That's with me doing the R&R. Labour prices are higher here.


  19. nekkidhillbilly

    nekkidhillbilly escaped mental patient

    the 200 metric idk why anyone would swap it a th350 for one. you get no overdrive and a very light duty trans. now the th350c i kinda liked. still rather have a 200-4r over any.

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