Multi-plate clutch options (split from another post)

  • G-E
    G-E
    Junior Member
    • 6320
    #1

    Multi-plate clutch options (split from another post)

    I'd venture since we can use z32 and z33 clutches if appropriately drilled, and the rb25 trans is the same, that we have options even from nismo and that's not including the ones requiring the pullpush conversion
  • Careless
    Careless
    Senior Member
    • 13279
    #2
    Re: My hybrid z unleashed

    G-E wrote: I'd venture since we can use z32 and z33 clutches if appropriately drilled, and the rb25 trans is the same, that we have options even from nismo and that's not including the ones requiring the pullpush conversion
    the only issue with the multi-disc systems available for RB engines will be the crank bolt size. they are larger than the Z31 and Z32 crank bolts. They are the same as KA24 bolts.

  • G-E
    G-E
    Junior Member
    • 6320
    #3
    Re: My hybrid z unleashed

    [quote]Careless wrote:
    Originally posted by G-E
    I'd venture since we can use z32 and z33 clutches if appropriately drilled, and the rb25 trans is the same, that we have options even from nismo and that's not including the ones requiring the pullpush conversion
    the only issue with the multi-disc systems available for RB engines will be the crank bolt size. they are larger than the Z31 and Z32 crank bolts. They are the same as KA24 bolts.

    Nothing a little sleeve couldn't fix?
  • G-E
    G-E
    Junior Member
    • 6320
    #4
    Hah ok since this is a NEW thread, let me list some of the basic data behind this:

    All RB motors are very similarly designed, this allows head swaps, and transmission swaps, bolt holes line up, all RB25/RB26 bellhousings are the exact same by all accounts, except which slave cylinder mounting bosses are tapped

    - RB20 rwd used fs5w71c transmissions (just like the z31 84-89 non-turbos) with an rb specific bellhousing

    - RB25 rwd     used the fs5r30a (just like z31 87-89 turbo) with an rb specific bellhousing

    - RB26 (GT-R model up until the r34 GT-R which was a getrag) came with an entirely different version 'r30a (no slip yoke)

    We know the input shafts are the same spline and pilot bushing size, and if the bellhousings are the same, then the whole front chamber holding the clutch is the same, allowing the exact same clutches to be used

    Skylines used push type and pull type clutches, the only exterior difference is the type of slave and how it's mounted to the bellhousing, some of the rb bellhousings have both sets of bosses cast into them (rb26?), to convert would only require drilling & tapping, then sourcing the right parts


    Unfortunately the vg bellhousing tapers off and has no extra bosses cast:


    Converting a z31 would therefore require some extra work, nothing crazy though