Register now to get rid of these ads!

What size rear end? 64 Impala with 700R4

Discussion in 'The Hokey Ass Message Board' started by guacamole, Nov 13, 2005.

  1. guacamole
    Joined: Sep 7, 2003
    Posts: 190

    guacamole
    Member
    from New Mexico

    Drove the 64 Impala project for the first time this weekend and was disappointed. The guy helping me was excited last week at it's power before I could get there. It is supposed to have over 400 ft lbs of torque and yet it does not feel any better than before I built an entirely new engine with a new 700R4 trans. It feels slow. I wonder if the standard rear end that it still has is just wrong for the application. I'm guessing it was about a 308. It's a 64 Impala that used to have a power glide with a 327, which is now about a 360 with as large of exhaust and intake as possible for the stock heads. The cam is a comp cam 262. The crank a balanced 350. The run in was very encouraging. The drive, discouraging.

    Wondering what anyone would recommend for the rear end on this car?
     
  2. jalopy43
    Joined: Jan 12, 2002
    Posts: 3,085

    jalopy43
    Member Emeritus

    I am sorry to hear that, after all that work. Yes, the stock rear ratio is too high for an overdrive trans. You need to swap out the tranny for a T.H. 350,OR swap out the rear for a 3:23 or lower gear. The '64 uses a drop out rear,and ring,and pinion gears may be hard to find. Then you have to get it setup right. If it were mine,I would swap the trans,'cause it would cost less in the end.:DSparky
     
  3. chopped
    Joined: Dec 9, 2004
    Posts: 1,824

    chopped
    Member

    I don't have the H.P. you do but when I went from the 350 trans 308 gear setup I add a 4:10 gear to the 700r4.
     
  4. rt66jt
    Joined: Dec 28, 2004
    Posts: 184

    rt66jt
    Member
    from York, PA

    You need more gear in your rear. Some searching should net you a '58-'64 rear with something like 3.73's. Don't give up, you're almost there.
     
    Register now to get rid of these ads!

  5. Mutt
    Joined: Feb 6, 2003
    Posts: 3,219

    Mutt
    Member

    You shouldn't have too much trouble finding a set of 3.55s used. Used 3.70s are hard to find and pricey. Richmond sells ring and pinion sets new. I have 4.11s to use with my 700R4.



    Mutt
     
  6. What you are experiencing ins the mismatch of components we sometimes get when buildin a car.

    the cam -in its lift and duration really will make the car run worse than the"old" engine.....
    You need to increase the stall or lower the rear to a 3/55 or a 3/73 gearset.
    a 308 is a good gear but with the cams inherent loss of vacuum[&low end snap] its not matching up......
    if you do much road tripping Id stop at a 3/.55
     
  7. guacamole
    Joined: Sep 7, 2003
    Posts: 190

    guacamole
    Member
    from New Mexico

    That's starting to make some sense. THANKS! I'd rather keep the stall where it's at and do the rear to a 3/55 as you suggest. Yes the car wil be road tripin'. I'm just guessing at it being a 3/08 but that was standard for some time back in the day. I guess...
     
  8. clutchxr
    Joined: Feb 4, 2007
    Posts: 5

    clutchxr
    Member
    from michigan

    How much power and abuse can a 64 impala rear and axles take? I am putting in a crate motor rated at 400hp 440torque. I am planning on putting in a eaton or auburn posi with either 3.73 or maybe 4.10 gears. I have a turbo 350 with a shift kit. will it hold up to this kind of power?
     
  9. Russco
    Joined: Nov 27, 2005
    Posts: 4,054

    Russco
    Member
    from Central IL

    Maybe its just me but a 262 isnt a big cam, it should make decent low end power you mentioned a big intake? you dont have a single plane intake on there do you? if so thats not helping I think a mild 350 with that cam and a 700 od trans should be ok with a 3.08 its not gonna be a stoplight killer but should abolutely be driveable.
    You need to post up some more info as to the rest of the engine.

    Edit:700r4 already has a much lower first than the powerglide plus you went from a 327 to 350 if it feels slower you got something wrong
     
  10. rt66jt
    Joined: Dec 28, 2004
    Posts: 184

    rt66jt
    Member
    from York, PA

    Those rears aren't the strongest, if the tires hook you might have a problem. Another issue is the center bearing for the two-piece driveshaft. Last I looked, someone was making stronger urethane bearings, look for one.
     
  11. clutchxr
    Joined: Feb 4, 2007
    Posts: 5

    clutchxr
    Member
    from michigan

    I have found a center bearing that is in a titanium mount which will handle the stress. I am worried about the rear though. I might just have to try and find a rear that will bolt in that will handle the power. If I go that route I will keep the stock parts around for my 64 biscayne that has the stock 230 6 cylinder. I am still researching weather to just go with a milder motor. thanks for your input
     
  12. Bgoodman
    Joined: Apr 2, 2006
    Posts: 178

    Bgoodman
    Member

    3.73's with a 235/75/15 thats the ticket with a 700R4
     
  13. HEATHEN
    Joined: Nov 22, 2005
    Posts: 7,592

    HEATHEN
    Member
    from SIDNEY, NY

    If you decide on 3.70 gears, look for a mid to late '50s Chevy 6 cylinder standard car; that's what they usually had.
     
  14. oaklandhotrods
    Joined: Feb 6, 2007
    Posts: 43

    oaklandhotrods
    Member



    I've put 500 hp through an early GM 12 bolt to the ground and it has never failed me yet. I'm not sure what's in a 64' Imp but it would deffinately be worth your while to look around for and early GM 12 bolt truck rearend. The best part about these rearends is that they're litterally a dime a dozen.
     
  15. Wild Turkey
    Joined: Oct 17, 2005
    Posts: 903

    Wild Turkey
    Member

    Did you also put taller tires on the rear? If so you've got a really tall ratio back there -- maybe good for top speed but not much for the streets.

    good luck -- sounds killer to me!
     
  16. 48ford
    Joined: Dec 15, 2001
    Posts: 412

    48ford
    Member

    I have 3;73s and running a 400 small block with 200r4, and 235x75-15s it works out well for me. the 3:08 is not going to cut it.
    Russ
     
  17. brokenspoke
    Joined: Jul 26, 2005
    Posts: 2,874

    brokenspoke
    Member

    I had the same problem..with a 308, switched to 355,wish i had gone to a 373...my 2cents
     
  18. clutchxr
    Joined: Feb 4, 2007
    Posts: 5

    clutchxr
    Member
    from michigan

    I think will just go with a posi carrier and a 3.73 gear. Hopefully the old 8.2 will hold up. I cant afford to buy a new one or have the know how to make anything else fit in unless I get one that just bolts right in. I cant weld or anything like that.
     
  19. Titanium? That is the most bunch of wasted money or marketing bullshit I have ever heard. The problem with the center bearings is not the steel sheel, it is the rubber that has to flex and eventually breaks. The urethane ones work better because they are stronger than the rubber. The problem is not the mount. If you are really concerned about the mount, add some stiffening straps to it.

    BTW, as the HAMB metallurgist, let me inform you that Ti is not necesarily any stronger than steel.
     
  20. Bort62
    Joined: Jan 11, 2007
    Posts: 594

    Bort62
    BANNED

    I had that same cam in an '85 305 w/ stock heads. It pulled really well but had nothing under 2.5k rpm.

    So, the gearing could be your problem - but its also possible that your engine is just setup way wrong. I would expect that combo to be a littlte soggy on the bottom end up pull well on top, regardless of gear.
     
  21. clutchxr
    Joined: Feb 4, 2007
    Posts: 5

    clutchxr
    Member
    from michigan

    I went through a few center bearings. Might have been problems with my old driveshaft because it broke right at the bearing. But I replaced the bearing at least 3 times in a short time. When I bought the car the rubber was shot on the first one. the replacement was made of cheap pot metal and broke right near the bottom the day it was installed. The second one ripped the plate where the bolts went in out after a short time. The current one is the original housing with new rubber zip tied all around to keep the rubber from pulling out. Seems to of lasted a couple of years. I talked to someone on the phone who makes the titanium mount and he told me its not for what I got. Its designed for use with a driveshaft with a slip yoke after the bearing. It is usually used by people will large suspenion travel like using hydros.
     
  22. In your defense, i also had a "new" carrier bearing that pulled the spot welds out from the bottom foot and the upper case piece. I just took it out and welded it back together with a full weld around the circumference of the foot piece and did not have any more troubles until I sold the car approx 1 year later. It was my daily driver 60 El Camino with serious lowering.

    Make sure you tighten the carrierbearing bolts with the weight on the suspension so you do not preload the rubber part. The ultimate fix is what you mentioned, putting a slip yoke in the rear driveshaft section.
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2020 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.