torque arm with coil overs. yes it works

Discussion in 'Suspension, Steering, Brake & Wheel Topics' started by purpleflame, Dec 28, 2010.

  1. K5JMP

    K5JMP Veteran Member Lifetime Gold Member

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    yeah, I'm having visions of Woody's mess when the plug welds broke, carrier rotated and it all came thru the rear floor... not cool.
     
  2. ZS10

    ZS10 Moderator Staff Member Lifetime Gold Member

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    I made one, actually a couple versions, got too tight in the tunnel for it and the drive shaft. Worked very well and will go back to it if/when I go coil over, just do some BFH work on the tunnel. Made it to fit a bracket that bolted to the center of the 9".
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    It did handle great on the road and hooked as well as any launch I've had with traction bars.

    purpleflame, I suggest you step back and have a look at what you're doing. The purpose of the arm is to control the diff, keep it from rotating. To do that it needs to be attached at two points, not just one.
     
  3. Rich Schmidt

    Rich Schmidt Veteran Member

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    I just wonder how with your method you would be able to adjust the instant center and correct the pinion angle. I was going to make a bracket with about 6 inches of adjustabilty at the front using a sliding front where the rod end mounts(like what is used on a wishbone) and have multiple mounting holes in the bracket that bolts to the frame. I would then need to be able to adjust the angle of the bar to keep the pinion angle correct. Obviously if I had the bar in the lowest position with the pinion angle set correct,and raised it to the top position the angle would be too high.

    A car set up with a torque arm that had the mount within 6 inches of the trans mount would almost definatly squart on launch and any car with this setup will pitch rotate a good bit. With a factory G body style 4 link the instand center is about at the center of the transmission,and those cars squat horribly and have no resistance to pitch rotation(leaving all bent out of shape) You would almost definatly need to add an air bag or spring preload to this type of setup.
     
    Last edited: Dec 31, 2010
  4. Rich Schmidt

    Rich Schmidt Veteran Member

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    Another setup would be to not make a torque arm at all,and just make a giant cal track type bar. fab one bracket that hung way low off the center section,with a single heavy wall tube that ran foward to the trans xmember and use a sliding mount on the front rod end(tube in tube slider like a wishbone uses) . Such a setup would have no real effect on the instant center,the slider could be adjustable using a jam nut so that at static height the bar wouldnt compress,but as the rear axle dropped or rose the bar could slide outward so it didnt bind the movement,but when the axle tried to twist it would stop it dead in it's tracks. Such a setup would have nearly no effect on instant center,but should stop the rear springs from wrapping any signifigant amount.

    As a side note,my 12 second street car has no traction bars at all,and runs on 10x26 slicks,and you wouldnt belive how much the rear of he car squats and the car rocks over from the torque. It leave like a G body Malibu more then a Camaro. It does work like a champ though.
     
  5. purpleflame

    purpleflame Veteran Member

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    K now after looking didnt know BMR finally built this have asked them about this idea a few times so yeah now they do it. funny thing is they only use a single bar just like I did. so now Im more prone to mine working right like I thought. notice they are using the bracket for triangulation like mine adjustable bushing up front and bolted bar in the rear,so guessing Im getting close. thinking there use of a watts link helps with twist as well? any thoughts?
     

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    Last edited: Jan 2, 2011
  6. purpleflame

    purpleflame Veteran Member

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    Man why couldnt they have told me they were working on this.
    It would of saved me a ton of time and work. although most of the stuff I already had only thing Ive made is the bars and brackets. makes me feel better about the whole thing working though.
     
  7. retorq

    retorq Veteran Member

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    Long pinion snubber!!
     
  8. purpleflame

    purpleflame Veteran Member

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    K wanna thank all you for the info and help on this I was getting frustrated and overthinking the whole triangulation thing and after more review and a great machinist friend of mine coming over we have come up with a killer idea for the torque arm gonna weld it up in the next few days and I'll post pics.
    got top and bottom triangulation and removing a heim joint or two and replacing it with bushings. will post up asap when bar is welded and in.
     
  9. purpleflame

    purpleflame Veteran Member

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    So its mocked up now and rolls on all fours, no hitting anywhere but need to still do bump stops and reinforce the top arm bracket then pull everything and clean it up for paint. still questioning the shock angle but seen other cars run them at a angle made sure both were the same. I have 6 degrees positive and negative for adjustment on arm as verified on ground with angle finder and am gonna change the trailing arm brackets to have some adjustments for anti-squat. welcome to criticism or thoughts.

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  10. sweetsoul

    sweetsoul Veteran Member

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    forgive me if i seem ignorant, but why the big bulky mess on the rearend?why could you not take the top bar back to a bolt on piece on the top of housing , and the bottom one back to the housing?the make an adjustable connection at the front to get pitch?dont cut my throat , im just asking.i been thinking of doing the same thing , i even got my 9 inch housing already.
     

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