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Simple question

Discussion in 'Early CJ5 and CJ6 Tech' started by Red, Mar 7, 2010.

  1. Mar 7, 2010
    Red

    Red Member

    Mesa, AZ
    Joined:
    Apr 14, 2005
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    128
    I just finished the rebuild of a 59 CJ5 and am curious. Given a rebuilt (completely) engine and the original T90 transmission, what should I get as a top speed on flat ground?

    [​IMG]

    [​IMG]
     
  2. Mar 7, 2010
    Patrick

    Patrick Super Moderator Staff Member

    Los Alamos, NM
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    Sep 22, 2002
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    What axle gears?
     
  3. Mar 7, 2010
    Red

    Red Member

    Mesa, AZ
    Joined:
    Apr 14, 2005
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    An obvious question, I don't know what the gears are installed. I suspect they are whatever was factory original in 1959 for a CJ5 with an f-134 engine. My distributor still uses centrifugal advance, and the generator still has a spot for oil to be added, the air filter is still the oil bath type, the oil filter is paper, and I have the proper (NOS) Carter YF carb; so I presume the gearing hasn't been upgraded.

    As a side note, I am disabled and my ability to work on the jeep myself is terribly limited. I used to do all my own work, but now I have to pay other to do for me. Most of my queries are going to be used to help my mechanic get things back to original without reinventing the wheel.

    Also, does anyone have any tips on checking for proper spring tension on the centrifugal advance? The engine pops and sputters (timing advancing too far too fast)
     
  4. Mar 7, 2010
    Patrick

    Patrick Super Moderator Staff Member

    Los Alamos, NM
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    Sep 22, 2002
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    Seems most were 5.38:1. That'll get you somewhere around 55-60 with the NDT's.
    Could have been 4.27: as well.
     
  5. Mar 7, 2010
    bkd

    bkd Moderator Supreme Staff Member

    K-Town Tenn.
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    Apr 29, 2007
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    most likely 5.38 gears......with out an overdrive you'd be pushing it at 45-50mph I would think
    Jim
     
  6. Mar 7, 2010
    Patrick

    Patrick Super Moderator Staff Member

    Los Alamos, NM
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    Sep 22, 2002
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    Oh. I was just going by what my Brother's F head with 5.38's was like with 29" tires.
     
  7. Mar 7, 2010
    bkd

    bkd Moderator Supreme Staff Member

    K-Town Tenn.
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    Apr 29, 2007
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    3,294
    your probably right I'm just guesstimating on the info provided, and I didn't like winding up my f-head
     
  8. Mar 7, 2010
    Patrick

    Patrick Super Moderator Staff Member

    Los Alamos, NM
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    My Brother won't take his over 4-4200 RPM, and he doesn't run it that high for more than a few hours.:D
    Really.
    Been driving it that way for 15 or so years.
     
  9. Mar 7, 2010
    Red

    Red Member

    Mesa, AZ
    Joined:
    Apr 14, 2005
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    Thanks for this info. Right now it's hesitating and sputtering at thirty to thirty five and I was certain that she should do forty-five to fifty at least because our M151's did that in Korea and along the grenz in Germany, they wanted to do more, but the suspension made them float on the road at those speeds.

    I have overdrive, (PTO too) but felt that I should be able to putter around better than I am before using it.

    Thanks again for the input
     
  10. Mar 7, 2010
    Howard Eisenhauer

    Howard Eisenhauer Super Moderator Staff Member

    Tantallon, Nova...
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    Nov 22, 2003
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    Without an overdrive you can get to 60 on flat ground but you'll be revving the engine pretty hard, it will tell after a while. 45 or so is really where it will be more comfortable at.

    With the OD you'll still only get to 60 due to the engine's torque curve vs. air drag but it's a lot easier on the engine.

    I've had the advance out of whack far enough that it wouldn't get above 30-35 (took off from red lights real nice though :)) but it didn't sputter, just ran out of poop. Could be you're not getting enough gas through...

    H.
     
  11. Mar 7, 2010
    jwjeep60

    jwjeep60 in process

    Sedalia Mo.
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    Apr 8, 2008
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    561
    between New york state and Missouri on 32"s no/od 5.38:1 and a tired engine the fastest i got was 70mph down hill, wide open throttle. 11-16mpg for 1000mi averaged 55mph.
     
  12. Mar 7, 2010
    mdbeck1

    mdbeck1 55 Willys CJ5

    Oklahoma
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    Aug 21, 2008
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    205
    Love the "anti-theft" device

    ..or is that the seat belt?
     
  13. Mar 8, 2010
    Chris Insull

    Chris Insull All roads lead me back to the beach... 2020 Sponsor 2019 Sponsor

    Misawa, Japan...
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  14. Mar 8, 2010
    Red

    Red Member

    Mesa, AZ
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    Chris:
     
  15. Mar 8, 2010
    Red

    Red Member

    Mesa, AZ
    Joined:
    Apr 14, 2005
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    Chris:
    Thanks for the useful link for speed calculation.

    The anti-theft device is my own design. I ordered a leg hold trap and welded it to a piece of 1/8"X1 inch stock. I use this when I'm out and about, it's quick to instal (I powered down the springs so it'll snap shut and scare the crap outta someone but won't actually harm them). And nobody seems to be anxious to sit on it. Even though it's powered down the seat is pretty unusable considering it's a standard shift. If you straddle it you can't reach the brake or clutch unless you're severely bow legged. With the trap held open your legs don't fit under the wheel.

    For here at the house I have a heavy streel clamshell that covers the entire steering wheel and spins freely. The damned thing weighs ten pounds but can't be cut off, they can't remove the steering wheel, thay can't steer with it on, so unless they have a tow truck they can't drive it, tow it, or push it as they can't move the steering wheel.

    I have my starter switch on the floor, three normal shift levers (two of em have neutral). plus overdrive (with a neutral) and PTO.

    I may be in a major metro area but there's hundreds of deer camps not too far away and lots of extreem off roaders all of whom would be happy to steal my prize and never have her on the road again, or, across the border to old mexico. I'm paranoid about loosing this.
     
  16. Mar 9, 2010
    unclebill

    unclebill Banned

    a sun blasted...
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    i have gotten mine to 55mph downhill.
    but it didnt like it.
    it purrs right along at 40-45
    i think of him as an antique tractor and we get along fine....
     
  17. Mar 9, 2010
    Red

    Red Member

    Mesa, AZ
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    Uncle Bill (et al.,)
    I agree, the CJ5 was advertised as a substitute for a tractor and should be thought of more like a mule than a thoroughbred. I'm hesitating in third with 2/3 of the accelerator's travel unused and only going thirty to thirty-five. I need the overdrive to keep up with surface street traffic going forty-five, and I have a need to go on the freeway for about an hour once or twice a month. I'm already planning ways to avoid getting in the way of bigger-faster things as the Phoenix metro area is noted for foolish drivers.

    Your advice has confirmed my suspicion that although I should avoid racing in the top fuel eliminator class, forty-five to fifty miles/hr without O/D is well within normal operation.

    What's the prevailing opinion on having a magnetic slow vehicle sign with small flashing light on the back of the Jeep when headed on to the freeway system here in town?
     
  18. Mar 9, 2010
    Thunderpig

    Thunderpig Member

    Parachute, Colorado
    Joined:
    Mar 28, 2006
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    259
    I avoid the interstate for that reason. My Jeep is comfortable at 45mph and I can get it up to 60 on flat, but I don't like to push it that hard for very long at all. I'm legal on the interstate, but with the speed limit at 75mph the closure rate is too high for comfort for me. If you HAVE to travel the interstate I think a slow vehicle sign is a good investment, albeit a little embarassing.
     
  19. Mar 9, 2010
    Hawk5274

    Hawk5274 Member

    Ohio
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    Nov 10, 2009
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    163
    With my :hurrican: I only take her out when I am not in a rush and can enjoy the area I'm going thru slow but sure....
     
  20. Mar 9, 2010
    CO64CJ5

    CO64CJ5 Member

    Littleton, CO
    Joined:
    Feb 26, 2007
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    125
    When we were both much younger, I got my CJ5 up to 70 once for a few seconds. We both survived, somehow.

    Probably helped to have the windshield folded down . . .:shock:

    Did I mention I was much younger then?:oops:

    I regularly ran at 60, but the geartrain noise was barely tolerable.
     

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