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IRS PINION ANGLE- ADVICE WHEN FITTING CUSTOM XMEMBER TO T56?

Discussion in 'VN - VP Holden Commodore (1988 - 1993)' started by UNLEASHED, Dec 3, 2017.

  1. UNLEASHED

    UNLEASHED Choose your weapon...

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    Hey guys. Anyone know if the front half of the tailshaft angle needs to counteract the irs diff centre pinion angle to avoid vibration at certain speeds??
    Looking into any input in this area as to spacing to alter the rear height of the gearbox??
     
  2. immortality

    immortality Moderator Staff Member

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    If you look at the centre mount for the drive shaft you'll note it is offset and it has marking on it, one way for IRS and the other way for the original semi-trailing rear suspension configuration. When used with IRS I believe it offsets the centre of the drive shaft to create a small angle across the pinions at each end.
     
  3. UNLEASHED

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    So basically just get the output shaft as close to centre as possible??
     
  4. immortality

    immortality Moderator Staff Member

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    No. You need a small angle across the pinions so they rotate. IF the pinion/drive shaft is perfectly straight the roller bearings in the pinion cups don't turn and will fail much quicker. By offsetting the centre of the driveshaft you are creating a small angle across the pinion at each end of the driveshaft resulting in a long happy life for the pinions.
     
  5. UNLEASHED

    UNLEASHED Choose your weapon...

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    Makes sense...Cheers immortality...
     

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