3.15 lsd

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jimmyspeed
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Location: riding a wagon wheel west

Post Tue Apr 07, 2015 8:51 pm

I took a punt on a diff hoping it was a rarer 3.46 but it turned out to be a 3.15

I think i have two options other than selling the diff, but would like to short cut all the research and ask if i can do the below -

A] fit the torsen in to the daily e36 328i - remove gubins and swap /is it that easy?

b] fit a m52 box on the back of the m20 turbo project car and reap the benefits of a stronger box? just to add i have bought a 618 pressure plate so don't know whether that fits in a m52/m50 box
jimmyspeed
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Joined: Sat Sep 08, 2007 11:00 pm
Location: riding a wagon wheel west

Post Tue Apr 07, 2015 10:23 pm

have been on the wiki page and the m52 gearbox would also need a custom prop so unless something turns up close its just added work

The terms - backlash and shims keep keep turning up whilst searching here but I'm unsure as to whether they need setting on a torsen? as there aren't any friction plates?

So I'm thinking i could maybe use an old preface 325i diff i have by removing the diff, leaving the pinion, then remove the ring gear and fit to the torsen and magically end up with an idiot proof rebuild?
HairyScreech
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Post Tue Apr 07, 2015 11:58 pm

Do what I did, e36 323/325 G250 box, the prop from the 36 and the diff.

Gives you about the ratios of a 3.91 on stock overdrive box.

Oh and for the zf box just use the 328 prop. there is enough spline to take up the length difference.
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
jimmyspeed
E30 Zone Regular
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Posts: 848
Joined: Sat Sep 08, 2007 11:00 pm
Location: riding a wagon wheel west

Post Wed Apr 08, 2015 11:27 am

Thanks guy, that rules out modifying the diff ratio but m52 gearboxes seem cheap on eBay so will see what crops up another diff or a suitable conversion parts

@ hairy - I'd really like a longer ratio ideals 3.46 or slightly shorter so the xf box seems the better option - can you use the stock e36 centre bearing ? As the wiki said you need a e30 one but maybe that's to use the stock fixing points which I could modify