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Help on diff gears

Discussion in 'LSx Development and Modification' started by bruzza, Apr 10, 2006.

  1. immortality

    immortality Home of the smoky breakfast Bacon! Staff Member

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    when selecting diff gears you should take into consideration the type of transmission as well as intended application.

    if you have a older 4speed auto (4l60e) which has a .70 overdrive you would be doing approx 2400rpm with a 4.11 diff @ 100km/h, however if you had a T56 trans which has .50 6th gear ratio @ 100km/h you would only be pulling approx 1700rpm.

    also, 1st gear on a 4.11/T56 equipped car is only slightly shorter then the factory 4l60e/3.07 combo 1st gear
     
  2. sus_calais

    sus_calais SIR 355

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    Prob best to go for a ride in a few cars with different gears if ya can! The lower ratio u go the more responsive but alot of the time, the less kms per tank u wil get..depending on driving conditions but as a general rule of thumb..
     
  3. walesy

    walesy Aint no family cruiser!!!

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    even the 3.46 make a massive difference with the big weight of the WH over the standard 3.07's, i got 3.9's aswell but never put them in yet, IMO there would be hardly a difference between 3.9 and 3.7's, i doubt you would really be able to tell really
     
  4. Jonno

    Jonno :)

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    4.11s ftw :)
     
  5. 03 VY

    03 VY New Member

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    hey guys, i know this thread started years ago but seems people are still making the odd comment so thought i'd chuck up a question....i'm thinking about changing diff gears to 3.46 in my vy ss auto, will this put the speedo out? i will be getting them installed perfessionally. cheers
     
  6. walesy

    walesy Aint no family cruiser!!!

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    the speedo will be out a little bit yes, but its quite easy to get it recalibrated
     
  7. 03 VY

    03 VY New Member

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    Thanks mate. Is it a difficult task and also can any performance shop recalibrate it for me?
     
  8. toey@carfx

    toey@carfx Detailing Junkie

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    for an auto like a wh is you would go either 3.46 out of a manual ss or 3.73 out of a manual hsv. the 3.46 is a good comprimise and easily found for sale 2nd hand where as the 3.73's would probly need to be bought new and fitted. these will rev higher on the hiway and would be more suited to around town and the strip
     
  9. eaton v8

    eaton v8 my little sleeper

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    It takes 2 seconds to do so get it tuned at the same time
     
  10. jakstas

    jakstas Auto Elec

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    Auto - 3.9:1. Seriously. Dont #### about.
     
  11. 03 VY

    03 VY New Member

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    Thanks guys. Wont be going 3.9's as I do too many hwy kms and dont want to compromise fuel economy. Will be conservative and go with 3.46's if anything
     
  12. QldKev

    QldKev Member

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    What did you end up going. I would still say go for 3.73 even with country driving. I don;t do much country and ended up with 4.11s behind my 4L60e and so far am loving it. Should have done it earlier.

    QldKev
     
  13. 03 VY

    03 VY New Member

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    I haven't put any gears in yet but when I do i'll be most likely chucking in some 3.46's and a baby cam at the same time. 3.73's seem to very popular with the auto's so i may consider these when the time comes
     
  14. tim005

    tim005 Yet Another VS Ute Owner

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    Go get it done at Total Traction Drivelines in Moorabbin.
    They recently rebuilt my LSD and they have worked on my mates ute also.
    They are straight to the point and give you genuine advice, I rate them highly.
     
  15. 03 VY

    03 VY New Member

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    Thanks mate, will give them a call when the time comes, I dont live far from there so could be handy
     
  16. tim005

    tim005 Yet Another VS Ute Owner

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    A quick google search would bring them up or shoot me a PM.
    Happy to help mate.
     
  17. Longy188

    Longy188 New Member

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    all the comments on here seem to be relating to V8's,
    my question is that is there a difference between the v6 and the v8 diffs ?? i have been looking at the diffs on ebay and it refers to:
    "WITH THE 3 BOLT DIFF FLANGE
    PLEASE NOTE THAT THIS DIFF HAS NO PINION SPIGOT BUT STILL FITS OK"

    can someone please explain it all too me,
    bascially will a v8 diff fit in a v6?
     
  18. QldKev

    QldKev Member

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    Yes the V8 diff will fit into a V6.
    The 3 bolt diff flange is what your VZ will have. Up until VT series 1 it was a round flange.
    The pinion spigot helps align the tail shaft onto the diff, really it is not needed and you won't find any difference in fitting it. If anything you will find it easier to fit without it as you don't need to slide the diff onto it.

    QldKev
     
  19. Vt_vic

    Vt_vic New Member

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    3.08 to 3.46 is not worth it in my opinion only if your getting it for free
     
  20. QldKev

    QldKev Member

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    +1

    When you spend 4hours under the car to swap it over, just do it once, do it properly.

    QldKev
     

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