Whats the best lsd for my car???

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Ya55lne
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Sat Apr 05, 2008 12:45 pm

Ive got a 320i with a 325i engine, gearbox has not been changed...although not 100% sure as i brought the car already with the 325i engine.
I found a lsd from a 320se 89 (same year as mine) and also another lsd which is 3.46 from an 86 m5 e28.

Which would be best out of both if any.....if neither which sould i look for?

Thanks
hongkongfuey
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Sat Apr 05, 2008 1:57 pm

i'm sure the 325 came with a 3.64, mine did, ive changed mine with a 3.91, i know others have done the same.
if there wern't people like me,
with cars like mine,
who would you put down to make yourself feel better?
gIzzE
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Sat Apr 05, 2008 6:21 pm

I think auto is a 3.64, manual is a 3.91 and a 320 is a 4.10, so it will be a little rev happy and might annoy sat at 80mph?

Not sure about the e28 lsd.
zaust
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Sat Apr 05, 2008 7:02 pm

64 is for the early high comp engine that has little extra and can strech it's legs a bit more so try it out and if you take to long going through the gears then stick with the 91.
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fuzzy
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Sat Apr 05, 2008 7:08 pm

higher number ratio will be quicker accelerating but have lower top end. depends if you want quick accelerationor quick top end? id expect the 3.46 to be a lower ratio than the other unspecified diff as that is more likely to be a 3.64 or above.
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Ya55lne
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Sun Apr 06, 2008 12:04 am

fuzzy wrote:higher number ratio will be quicker accelerating but have lower top end. depends if you want quick accelerationor quick top end? id expect the 3.46 to be a lower ratio than the other unspecified diff as that is more likely to be a 3.64 or above.
hmmm well i would rather quicker acceleration...not fussed about going 150mph!!
gIzzE
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Sun Apr 06, 2008 12:41 am

Look at it another way, do you want to be continually changing gears round town??

A 3.64 lsd in a non sport 325i will give the same feel as a sport 325i, as the gear ratios are different, putting a 4.1 diff in a non sport means you will only get to about 49mph in 2nd before needing to change gear, a sport gets to 56 mph.
If you put a 3.64 lsd into a non sport you get to 56.6 mph in 2nd, so pretty much the same as a sport.

Sat cruising at 80mph you will have 4300rpm with a 4.1 diff and only 3700rpm with a 3.64 diff. This is the difference between 28mpg and 34mpg in my car, so another thing to consider, if it is an everyday car.

I would guess that a 4.1 diff would feel more brutal but not sure if it would be the one to live with daily.

Anyone tried both?
Last edited by gIzzE on Sun Apr 06, 2008 1:28 am, edited 1 time in total.
Andy325i
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Sun Apr 06, 2008 1:05 am

To the OP, I'm pretty sure the E28 M5 diff is a large case (rather than the small/medium cases) used in the E30

Andy
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Ya55lne
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Sun Apr 06, 2008 1:21 am

Thanks for that gizze....i dont want to be changing gears every two seconds!! I tink i will have to go with the 3.64 then.
bazeebond
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Mon Apr 07, 2008 11:19 am

Cheers Gizze, was searching for some Diff advice last month and decided a 3.64 would be the best compromise for my 325i SE daily driver. Some good points there.

Just need to locate a good condition one though... Although, there's always a brand new Quaife! :mad:
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