A dumb question about a dumber video...

Discussion in 'Technical' started by facelessnumber, Jun 25, 2012.

  1. facelessnumber

    facelessnumber Drew Pittman

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    I'm hesitant to even show this. I went to the drag strip, and it wasn't embarrassing enough that I ran a 14.7 due to my horrific traction problem, nor was it enough that on my second run, I just botched the launch entirely and decided to put tire smoke down the whole track... No, it had to get worse.

    On my third run, I reasoned that I should have burned out a little on the previous one, because I did on the first one, just enough to get the water off the tires, and I was able to launch better. ("Better" being relative. I mean "better" in the same way that a colonoscopy is better than a colostomy.)

    So I burned the hell out of that right tire. Yes it was pathetic. But what's this? For a second there both tires spun. :hmmm:

    So here's my question: I've not seen an open diff do that. Clearly it can. Or does that mean I might actually have a worn-out Trac-Loc in this rearend and it just needs clutches?

    I need to do some rearend work before I go back out there, obviously. I haven't decided what direction to go but I'm strongly leaning towards the Explorer 8.8 swap. But if it turns out I already have that elusive 8" Trac-Loc I may just try to fix that and order a new gear set.

    What says the MMB?

    (Y'all please just ignore everything in that last video after the burnout, especially the part where I stage with my rear wheels, ok?)
     
    Last edited: Jun 25, 2012
  2. Joe Dirt

    Joe Dirt BBF life

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    A open rear end has the capability to spin both tire if the housing binds or the shock load is great
     
  3. facelessnumber

    facelessnumber Drew Pittman

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    I'm just gonna go with "the shock load is great."

    Ah well, wishful thinking. I didn't really think it was likely, but I sure would have felt like a fool if I discovered a Trac-Loc in that diff after replacing it.
     
  4. Jsarnold

    Jsarnold Senior Member

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    Raise the rear of the car so both rear wheels are off the ground. Put the transmission in Park (or in gear if its manual). If you have limited slip you won't be able to turn a rear wheel. If you have an open rear end, the other wheel will turn in the opposite direction.
     
  5. facelessnumber

    facelessnumber Drew Pittman

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    Yeah, I've observed that several times. Just figured a worn out LSD might do the same.
     
  6. ford84stepside

    ford84stepside Lone Wolf

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    It will. I had a 4X4 pickup that I owned for several years that I didn't even know had a lsd until my son had it at school shop and they pulled the chunk because it was leaking. The clutches were worn slap out, and it did the one wheel pull. If they hadn't of pulled the chunk, I'd never knew.
     
  7. mavgrab302

    mavgrab302 MCCI Florida State Rep

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    Mine is an open 8 inch and the 1st time I played with it,,, it left two equal marks in my driveway (still there) and I thought wow I have a LSD,,, Nope one wheel peel ever since... :(
     
  8. scooper77515

    scooper77515 No current projects.

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    The tire with the least grip will spin. If the grip is exactly even at any time, both tires should grab (or both spin).

    That will happen rarely, due to weight differences and forces applied differently between the tires.

    But, if logic is applied here...if you could somehow make the force to each tire exactly the same all the time through your run, both tires would grab. No slip, since one tire is not getting less force than the other.

    Maybe some computerized weight distribution program and setup, similar to a Segway that would constantly calculate how much pressure is on each wheel and move weight around to correct it and keep it even?

    You should be able to pull something like that together for a couple hundred grand.

    Or slap in a $300 posi differential and be done with it! :tiphat:
     
  9. facelessnumber

    facelessnumber Drew Pittman

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    Unfortunately the ones you can just "slap in" aren't $300, and the ones that are $300 take a good bit more than a slap... But that's where I'm going with it. LSD and gears. Time is my main problem. I can't afford the ones that don't take time, and don't have time to install the ones I can afford. It will happen though, it's on the top of the list.

    Well, right under the u-joint I twisted apart tonight...
     
  10. scooper77515

    scooper77515 No current projects.

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    When you finally hook, I have a feeling you are going to start "twisting apart" lots of things, so be prepared to starts spending money upgrading and replacing stuff.
     
  11. 71gold

    71gold Frank Cooper Supporting Member

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    the drag strip is where you go to find the weakest link...:tiphat:
     
  12. facelessnumber

    facelessnumber Drew Pittman

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    Of that I am certain! I've got a spare C4, flexplate, converter, intend to get a spare driveshaft, (probably going to run a fox DS and keep my old one around with a yoke and a u-joint on it just in case) I'll keep my old rearend unless somebody offers me good money for it...

    And if I break anything else... Well I guess anything I might break in a launch other than that stuff will mean the body's ruined.
     
  13. Joe Dirt

    Joe Dirt BBF life

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    Your not going to break a stock driveshaft unless its been structurally compromised.
     
  14. facelessnumber

    facelessnumber Drew Pittman

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    Yeah I know, I just figured if I've got a yoke and a u-joint on a driveshaft ready to go it's faster than trying to fix one at the track. I'm not going to be taking transmissions and such with me, but I figure it's no big deal to sling a driveshaft in the back of a friend's truck along with the tools I'm already taking.
     

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