325 e36 saloon diff ratio? is a 318 diff, shafts etc a good upgrade?

Thread in 'Technical Questions' started by Clive, Mar 25, 2012.

  1. Clive

    Clive Active Member

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    As title really.Wondering if the diff set up would be a good upgrade? How much am I looking to pay for the shafts and diff etc??
     
  2. WSA

    WSA Member

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    318 diff is small case from what i remember fella?
     
  3. Clive

    Clive Active Member

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    Yes it is as far as I know, hence why I said about shafts :-)
     
  4. RevErTrevor

    RevErTrevor Member

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    Yeah it's a decent enough swap, it goes from 3.15 to 3.43.

    You'll need the diff and shafts, and you'll need to loosen the nut at the centre of the prop and slide the prop further towards the new diff so it'll bolt up.

    Probably looking to pay £70-£80.

    Hope this helps.
     
  5. bell

    bell Without patience

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    i currently run a 318 diff setup on my 325 it makes the acceleration loads better but in turn your mpg goes through the floor.
    appart from acceleration any other reason why your looking to swap? if its to make life easier put your right foot down a bit.
     
  6. Mike@TDSW

    Mike@TDSW Active Member

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    First thing I'd do to a 323/5/8 drifter. Well worth the effort IMO.

    Bell I ran my 328 on a 3.73 diff for a while and it didn't alter the average mpg of 29 (inclusive of 2 drift days) over the time I used it. That was doing like 4.5k on my 80mph run to work lol.
    Ive got a theory that Ultimately it takes a certain amount of energy to move a set mass at a set speed with a set amount of resistance. The only increase in energy required is to make the engines internal components move a bit faster.
     
  7. mushtafa

    mushtafa Member

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    I don't understand how people can run small case diffs and skinny shafts?? I've broken 2x shafts on my 325 (welded diff) and a mate of mine destroyed a 318 diff on his 325 (open diff).

    I've got a diff ready to weld, but can't see it / the shafts lasting long?

    Sent from my Desire HD using Tapatalk
     
  8. Mike@TDSW

    Mike@TDSW Active Member

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    I had a small case diff on mine for 2-3 years and many many drift days. No issues. Was even drifting top of 4th around gerrards with lots of clutch kicking.
    I snapped a 540 shaft drifting out of a junction once though lol.
     
  9. Mattyboi

    Mattyboi Active Member

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    I'm with you on this. I had a 325 (welded) diff casing explode into a million pieces driving down a dual carrageway and now I'm abit worried about getting my new diff welded again as when i called around everyone i spoke to was suprised i didnt have a spare like it was the most common thing to happen in the bimmer world.

    Is that the case mike or was i just unlucky?
     
  10. Mike@TDSW

    Mike@TDSW Active Member

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    I've never broken a diff and only ever broke one shaft.
    I've known people that have though but I've owned more bm's than anyone I know.
     
  11. Mattyboi

    Mattyboi Active Member

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    Well i guess I'll just stop being a pussy then!
     
  12. bell

    bell Without patience

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    the diff out the back of my touring came down from scotland on a maroon saloon that ren sold, hed abused it then liam abused it for 2 years i then abused and currently still am, its a welded 318 diff also.
    i just fancy some longer gearing if im honest
     
  13. Rhys_sx

    Rhys_sx -NightWalkers-

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    is are old 325 still on the same diff and shalfs mike , if is thats a example of how they last . i only ever snapped one shalf and that was a stock 328 ( welded diff ) doing a tight U turn on grippy concrete. keep a spare pair in the sheld if u really that worried as they only take 20min to change on the floor if u break one
     

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