Hey up,
Thinking of swapping out my clunky diff but I'm unsure what ratio it currently has. Its a 325i cab, so I know its medium case, but the ratio I'm unsure of. I'm guessing its 2.91 as this was paired with the autobox?
Also, my cab is an automatic, would I benefit from an LSD?
-Mcbonio
325i differential options
Moderator: martauto
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RichIS
- E30 Zone Regular

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- Joined: Sun May 07, 2006 11:00 pm
- Location: gloucestershire
2.91 seems wrong to me 3.91 maybe? as for a lsd unsure of the benfit would be so noticeble with a auto box
Injections nice....but I'd rather be blown ;)
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B7
- E30 Zone Team Member

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- Joined: Tue Feb 13, 2007 11:00 pm
- Location: Surrey / West Sussex
It'll almost definately be a 3:73. Every convertible i've seen has had this ratio.
LSD is always an upgrade no matter what transmission you have.
There are 3 ratios which are associated with 2.5's.
3:91 from a tech 2 sport. These pep them up nicely off the line
3:73 convertible and Alpinas choice for the C2 2.7's (IIRC)
3:64 from the saloons (and Tech 1 sports) which give a lower RPM on a motorway.
Basically you take your choice as to what you want to do with the car and how you want it to perform.
LSD is always an upgrade no matter what transmission you have.
There are 3 ratios which are associated with 2.5's.
3:91 from a tech 2 sport. These pep them up nicely off the line
3:73 convertible and Alpinas choice for the C2 2.7's (IIRC)
3:64 from the saloons (and Tech 1 sports) which give a lower RPM on a motorway.
Basically you take your choice as to what you want to do with the car and how you want it to perform.
B7's Motto. "If it's French, BURN IT!!!!!!"
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mcbonio
- E30 Zone Squatter

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- Joined: Sun Feb 12, 2012 11:00 pm
Excellent info B7.! Thank you!
