S15 Diff on an S13??

Thread in 'Technical Questions' started by pieface, Jan 26, 2011.

  1. pieface

    pieface Go!Go!Auto

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    Right, did a little search on here, but it didn't throw much up.

    Basically I'm looking into diffs, and want to do my homework. Spoke to a mate and he said get an s15 diff as they are semi-helical and are better than the S13/14 LSD.
    But will it fit?
    Is it a case of using the complete prop, or not?
    Is it an easy task, or more of a ball ache than its worth?

    opinions welcomed.

    Cheers in advance.

    Pieface :thumbs:
     
  2. RyanH

    RyanH Lacks skills

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    I think the diff mounting point on the S15 prop is the same as the S14 (i think it's just the gearbox end that's different to suit the 6 speed).

    Not sure how much better than the VLSD for drifting use though.
     
  3. zeppelin101

    zeppelin101 Member

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    Helicals are crap for drifting, you need a proper locker.

    Not much out there that is better for driving fast though.
     
  4. andeep

    andeep Member

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    The S15 helical is a straight drop into the S13 casing with the S15 output shafts. The crown gear has the same ratio as a manual S14 and the grown gears are the same as any R200 diff. But the crown gear bolts are different on the S15, so you need to make sure you get one with the bolts.

    As said, the helicals are crap for drifting, but very good for grip driving.
     
  5. pieface

    pieface Go!Go!Auto

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    Ah ok, so would I be better off buying an S14/a diff, as they were LSD as standard iifc
     
  6. andeep

    andeep Member

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    It depends on what you want the car for. If you want to drift, get a welder or a 2-way. If you want to grip drive, get a helical or a 1.5way.

    The majority of the S14/a viscous diffs have opened up by now.
     
  7. pieface

    pieface Go!Go!Auto

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    Yeah, If I go S14/a route, I'd be looking for a low milage one. Don't really want to go down the welded route, and at the moment I don't have enough money for a 2way, but I will buy one EVENTUALLY.

    Basically I'm wanting a diff that will do me until I buy my 2way, but as I said, I don't want to go down the welded diff route.
     
  8. andeep

    andeep Member

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    Then deffo don't go for a helical - like it's been said they aren't great for drifting.

    A welder will serve you well until you go for a 2-way, why is it you don't want one?
     
  9. superclarkey

    superclarkey DORITECH MOTORSPORT

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    Most 2 ways you buy are like a welded diff anyways..

    If you want a proper welded diff done, give me a pm :)
     
  10. pieface

    pieface Go!Go!Auto

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    Will keep you in mind Clarkey. In fact may send you a pm with a question or 2
     
  11. andeep

    andeep Member

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    If you get someone to weld the diff properly, its basically a 2-way (except it won't open under no load).

    When I say properly, I mean someone to fully dismantle the diff (take all the bearings off) and weld it. Usually when a diff is welding while in the casing the heat from the welding cooks the bearings and they start to whine very loudly.
     
  12. Waveydavey

    Waveydavey Member

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    What affects will welding it have on day to day use? Id get mine welded up but dont want it being a death trap.
     

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