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TH 700R4 tech.... and install into 57 Chevy

Discussion in 'The Hokey Ass Message Board' started by rat bastad, Jul 27, 2007.

  1. Any HAMBERS run this trans (non lockup) behind a 283 in a tri five?

    I recently scored a real nice 57 Bel Air matching numbers longroof surf wagon and want to keep it looking almost stock apart from the altitude adjustment and a nice sounding hyd cam.

    But I'm looking to maximise efficiency, 1st gear acceleration, and OD economy on the highway in the wagon and I know the Glide it comes with has a real tall 1st gear and weighs a shitload.... so I figger maybe a 700 R4 could be a viable swap. I know it has been done successfully and parts are available to make it look like a factory install from the column gear indicator to the trans mount.

    1st gear ratio in the 700 R4 is 3.06 with a 4th gear/ OD of .69 - this will help the small cube motor really wake up and maximise its efficiency.

    Engine is a 283, 10.00:1 CR, bowl ported/shaved power pack heads, port matched Corvette dual plane intake,, 57 Rochester four barrel (450-500cfm), 450" lift/218@.050 hyd cam, ported rams horn manifolds,and 3.36:1 rear gears.

    I know a TH 350 is a leap in the right direction but I'd really be interested in TH 700 R4 for a mild application like this and for max economy. That 3.06 first gear will wake that sucker right up too.

    This thing looks totally standard from the outside but I want to improve its efficiency as a daily driver and that stock Glide I feel wont cut it.

    I know the earlier 700 R4s had dramas with line pressures and weak 27 spline input shafts that were upgraded to 30 spline and overall were improved from the mid 80s on.

    So can someone school me on the the possibilities of this swap and as to which trans to get my hands on?


  2. Deuce Roadster
    Joined: Sep 8, 2002
    Posts: 9,519

    Deuce Roadster
    Member Emeritus

    [​IMG] [​IMG]

    I just bought the kit ... from these folks ... to solve the TV cable issues.

    Their kit uses a lot of Lokar stuff and their own carb arm adapter.


    You would need side motor mounts on the SBC ... IMHO to do the 700R4 swap. Also ... you need starter mount bolt holes on the block. I do not believe original 57 blocks have these needed items ...

  3. Rat, Just did the 700r4 swap in my 55 , I kept the original front mounts and added the mid bellhousing mounts along with a trans mount , was an easy swap and works great,70 mph on the highway equals to about 1950 to 2000 rpm, got to be good for gas mileage, I did substitute a 350 v8 for the six cylinder so I am not familar with the starter setup. sent you a pm
  4. Thanx for the heads up. But what exactly is this TV cable? DOH !!

    Does it pick up the History Channel lmao ???

    Seriously, what is its function and how does it work? Also, what is the deal with the starter motor?

    Walrus, check your PMs...


  5. nexxussian
    Joined: Mar 14, 2007
    Posts: 3,240


    TV = Throttle Valve. It is how the 700R tells how far you have your foot in it. It controls a valve inside the trans that varies line pressure and as a result shift firmness and shift points. A maladjusted TV cable can make the trans shift poorly and not at the desired points or if it is even further off you can burn up the trans in short order as the 700R does not have a vacuum modulator to sense engine load through manifold vacuum as some other transmissions do (IE TH350). That is why there are several adjustable cable setups to put the 700R in places it wasn't designed for originally.
  6. Bluesfella
    Joined: Apr 30, 2004
    Posts: 146


    The TV cable is arguably the most important part of the swap when switching to a 700R4 trans.

    (I just did this swap in my '55 a few weeks ago, though I have a later-model V8 in mine.)

    The TV cable controls the Throttle Valve have to have it set correctly or you will burn up the trans. It looks like a kick-down cable for a TH350 trans, but it's more important than that.

    I don't know about the starter questions, but I really like the 700R4 trans.

    Why would you want non-lockup?
  7. Bluesfella
    Joined: Apr 30, 2004
    Posts: 146


    Oh, and I didn't use this system for the TV cable, but I know a lot of folks who have and were satisfied with it:
  8. nexxussian
    Joined: Mar 14, 2007
    Posts: 3,240


    Do you want to run it non lockup for some reason? It will get better economy and run cooler in OD if you let it lock the converter. It can be done as simply as a switch on the dash all the way up to a wiring kit that includes a vacuum switch to unlock the converter at higher throttle settings.
  9. Moonglow2
    Joined: Feb 4, 2007
    Posts: 658


    You are correct about the later 30 spline input shafts being the better tranny. Both it and the 200-4R went thru several improvements the longer they were offered.

    Check out Bowtie Overdrives for tech info and they have a TV kit that eliminates all the guess work for adjusting the TV. A fellow HAMBer on here offers a lock-up kit for the TC. Opinions differ between tranny builders whether to run a lock-up or not.

    Pay attention to Bowtie's article on checking line pressure before attempting to drive the car. Assuming you can resolve the starter hookup problem find out your rear gear ratio. I think most 57s ran either a 3.36 or a 3.55 . Short stroke sbc's need more rpms at cruise speed (at least 2000) than their longer stroke cousins to get any mpg benefits.

    The formula for determining this is as follows:

    mph x final drive ratio x 336 / tire dia in inches = rpm

    Example: At 70 mph using a 700-R4 which has .70 overdrive ratio, a 3.36 rear gear and a 26 in.tall tire the math would look like this.

    70 x 3.36 x .70 x 336 / 26 in. = 2127 rpm

    Good luck - let us know how it works out.
  10. 1950ChevySuburban
    Joined: Dec 20, 2006
    Posts: 6,188

    Member Emeritus
    from Tucson AZ

    1987 to 1991 trannys are best. Make sure it has 2 valve bodies.
    I'd buck up for the better 13 vane pump, the reinforced sun shell and the Corvette servo, among other things.
    And yes, TV cable adjustment is critical!
  11. Great info guys....thanx a bunch. Im gonna look ino this some more. Any more info?

    BUMP !!

  12. stickylifter
    Joined: Feb 21, 2005
    Posts: 1,268

    from Detroit

    You'll definately want to hook it up so the converter locks up. Slip in the converter causes more heat. Also, your mileage will be way better in cruise gear. You can hook it up with a kit from these guys: Bowtie Overdrives. There is a lot of great info on the site as well.
  13. Deuce Roadster
    Joined: Sep 8, 2002
    Posts: 9,519

    Deuce Roadster
    Member Emeritus

    1957 Chevrolet starters ... bolt up like this ...


    To a bell housing like this ... Ford to SBC adapter shown ... but the adapter shown uses a starter like the one on your 57 originally came with


    Later engines ( like the ones that 700R4's came bolted to had a starter provision on the block. Upper left hand corner of the photo


    Check your starter ... if the bolts go into the bell housing ... and not into the V8 block ... you will have to figure out the starter deal :mad:
  14. Thanx for the info DR....Ill explore this a bit further an thanx to all who posted !!

  15. Enginetuner
    Joined: Dec 8, 2006
    Posts: 192


    You really want to keep your lock up, not only for the economy, but in over drive there is not enough line pressure without lockup and a pontential for burning clutches is present. Some trans guys are enlarging the oil pressure ports to gain more volume and pressure while in o/d and not having lock up. Lock up can be applied with a switch as mentioned earlier or you can have it engage and dissengage with pressure, talk to your tranny guy.
    Ever thought about the 200 trans, alot lighter and just as dependable with a mild engine...just a thought.

    Joined: Jul 27, 2007
    Posts: 9

    from VIRGINIA

    I Think Ecklers Classic Chevy Or Danchuk Manufacturing Has Everything You Need For This Swap.
  17. Hey Frank sounds cool...any pictures....?


    (PS< last two photoshoots this weekend!!!)
  18. mark 55
    Joined: Oct 12, 2006
    Posts: 110

    mark 55

    Did this same swap in my 55 chevy wagon. Just drove from Louisiana to Bloomington Illinois and back. 20 mpg and no problems.
    I run a 64 vintage 283. It's the way to go. Pm me if you need any additional info.
  19. Mark thanx for the tip, Ill probably be in touch at some stage in the near future.

    Maiki, Ill put up some pix soon and some detail on the ride.

    PS: Got some pix for me?

  20. pasadenahotrod
    Joined: Feb 13, 2007
    Posts: 11,776

    from Texas

    My 57 PowerPack V8 had been drilled for the "modern" starter and worked quite well hooked up to a built air-cooled PowerGlide from a 62 Nova in my Old T Roadster. Many engines are already drilled for the "new-style" starters even if they have the old iron Powerglides behind them.
  21. I did the 700-R-4 in my 51. I didn't buy any lock up Kit due to Cost related $70.oo up). I chose to use a $3.oo Relay from Radio shack and link it through my Brake light switch. No Big Deal. The relay has Full time Batt. Power with Key on to the Tranny. The internal lock up cylonoid does not get a signal untill your shifted into O.D. so no problem there. It only locks up the Converter after the shift to O.D. when you touch the Brakes and the brake lights come on it opens the relay and cancels lock up. It's real Basic and Cheep, works Grate.
    The Wizzard
  22. plym_46
    Joined: Sep 8, 2005
    Posts: 4,018

    from central NY

    my 700 R 4 is out of an 86 or 7 Caprice. It has three wires coming out of a connector in the drivers side. I was told one was for ground, one is for non OD lock up (third gear) and the other is for OD lockup (4th gear).

    Can you post a schematic of how you hooked in your relay? sounds like a simle solution but I don't know which wire on the trans is which.
  23. You only use 2 wires to the Tranny. The plug has A,B,C,D, marked terminals (be gental opening the cap on plug) A and D are all I used. D goes to Ground. I used a 5 pin Relay and wired it so to pass power through with key on and a 10 Amp fuse in line. That's what G.M. uses in ther stock fuse panel. I used a B+ signal from brake switch to Open relay and remove power. No big deal.
    The Wizzard

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