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The new FJ 73 Build

Discussion in '70-Series Tech' started by Alex gee, Jul 7, 2015.

  1. Alex gee

    Alex gee

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    Started building bits for a Shackle reverse today, trying to get rid of the low hanging long shackles from out front.

    front shackle,

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    new front mount, will go up a good 50mm at least, have the choice of possible moving it forward a little if needed.

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    New rear shackles, using standard 70 series bushes, that will use the existing rear hanger, still havent drilled them, will see where they need to end up after a full mock up.

    [​IMG]

    [​IMG]
     
  2. cruiserpilot

    cruiserpilot

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    From my experience with my SOA FJ40 on 38.5/14.5B15" TSL SX's. I did a shackle reversal while it
    did improve road manners it was not good for flex.
    On the rear I had shackles like that with the center cross bar. I cut that cross bar as it really effects how the springs
    flexed and limiting effect on how the whole truck flexed. I found the shackle has to flex independently from one
    side to the other. Just thought I'd pass it along. Its in getting rebuilt and I'm putting the shackles back up front
    as I go along.
     
  3. Alex gee

    Alex gee

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    Front mounts removed.

    [​IMG]

    Spacers tube and common rod to ensure a nice line up,

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    Tube gussets added.

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    shortened and revised the rear shackles for a better angle and sweep.

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    Before spring rotation

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    Good angles at full flex, this is afetr a spring rotation to move the axle forward approximately 100mm, note no front axle, need to legthen and long slip it.

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    sits like this now, tyre is way forward, much better aproach,the new arch of the springs really benifits the tie rods and drag bar clearances as the move away from each other now.

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    With the axle shift so far forward i had to move the shock mounts, made some tubular mounts,

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    very happy with the out come, have gained back 90mm in height, increase front clearance, much less wondering from the big shackles out front, and only lost less than 40mm in flex, seems to eat bumps much nicer now with the suspension pivotting back not forward.

    [​IMG]
     
  4. ALEXY

    ALEXY

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    how much slip on the front shaft you expect when axle will flex?
     
  5. cruiserpilot

    cruiserpilot

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  6. Alex gee

    Alex gee

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    Trail gear 12" long slip yokes for the new front shafts,
    These things are stout,

    should easily cover it,

    [​IMG]
     
  7. Alex gee

    Alex gee

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    fitting tyres,

    [​IMG]
     
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  8. Alex gee

    Alex gee

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    Sitting pretty,

    [​IMG]

    15 PSI all day

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  9. Alex gee

    Alex gee

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    Been pretty busy of late,
    But kicking goals, am back on all fours in 4wd non the less,

    Trussed and gusseted the rear axle,


    [​IMG]

    front shaft mocked up, floating front, Ended up with hilux front and rear single cardon joints and redrilled flanges to suit,

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    full down with a good few inches for compression,

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    finished, at full flex no binding,

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    Frame notched for drag bar clearance,

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    re-inforced and plated,

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    numbers are good,

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  10. cruiserpilot

    cruiserpilot

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    I can see it works, but I've always been told that the front diff angle should be set a little
    more direct that yours seems to be. So asking why didn't you rotate the angle on the pinion?
    Amazing work, J
     
  11. Alex gee

    Alex gee

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    For single Cardans top and bottom its ment to be as close to parallel as possible, i am currently 4 degrees off parallel,

    If you run a double cardan on the transfer you need rotate the pinion angle to 0 ish,

    I toyed with a rotate but with the hydro assist and gussets it was going to be a nightmare,

    [​IMG]
     
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  12. cruiserpilot

    cruiserpilot

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    Thanks, on my FJ40 with the SOA I rotated it up and then used a double cardon. Too cheap to buy a new
    single that would have suffered through that angle at the time. J
     
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  13. Alex gee

    Alex gee

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    Always a little nerve racing heading out with newly built parts, I pretty much had the full front end to test out as well as the wheel and tyre combo and was flying solo,

    All went well, i didn't air down just ran the crawlers at 15psi and they performed very well.
    The new front spring set up seems to be a lot softer over obstacles, the hydro assist worked nicely , a bit sluggish at times may need to get a bit more pressure to the ram,

     
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  14. cruiserpilot

    cruiserpilot

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    Seems like the suspension is working as well as any I've ever seen. I only saw rear wheel spin, were you in
    2wd most of the time on the video?
     
  15. coldtaco

    coldtaco

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    that v8 sounds real good :)
     
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  16. tommybj73

    tommybj73

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    Hey mate,do you run the crawlers at 15 psi in the road?I have noticed that they have a huge crown on those tyres
     
  17. Alex gee

    Alex gee

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    I think a handful of the clips where 2 wheel drive, the motor is still real twitchy power wise something im stil getting used to.
    Need to sort a front locker which will even out the delivery a lot and then some transfer gears or twin cases to knock it back a heap.

    The tyres are at 15PSI all the time, I only drive to the tracks so its very light usage on the road, They could have benifited from a drop in pressure on the rocks definately but i couldnt be bothered, LOL
    They seem to crown a bit on the top but balloon a fair amount on the bottom.
    Awesome tyres the width is madenss,
     
  18. Alex gee

    Alex gee

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    What started as a little shift to look for a better shackle angle, turned into a full spring rotate arch rebuild and so on,

    Ended up moving the axle rearward by at least 100mm.

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    Chopped and re-plated,

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    more gains and have further lengthened the foot print,

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  19. Alex gee

    Alex gee

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    Had an interesting outing on the weekend,
    Un earthed a few problems,

    Sprung a powersteering leak,almost had a flat battery and,

    Turns out the front shaft was too long and my suspicions of the thud were confirmed and i had to shorten it,

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    Neglected to have a good look at the rear shaft length and ripped it out through a bog hole.

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    Shaft out re set and good to go, just

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    A side by side of the gains from the extended wheelbase and adjusted bar and so on,

    [​IMG]
     
  20. Alex gee

    Alex gee

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