LSD Query again - tested and still unsure, HELP ME!

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Dan318-is
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Post Thu Jul 21, 2005 5:48 pm

ok so i jacked the rear of my car up and put it on axle stands. i was told that if i spin one wheel one way and the other wheel spins the opposite direction, i only have an open diff. well i spun one wheel and the other one stayed static :?

what does this mean??

I then tried the other technique i was told about; let one side of the car down and tried to spin one wheel, and it did spin, im so confused, does this mean i have an LSD or not, i crawled under and looked but cudnt decide - iv got pics if someone wonts to help me or needs images?

Also, i put the handbrake on at the start while both wheels were in the air and could still spin the nearside wheel - does this mean the handbrake shoe is gone?

please help me on this guys as i need to no whether to add an LSD to my list of things to buy

thanks 2 n e one who helps!
Ant
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Post Thu Jul 21, 2005 6:30 pm

OK, car out of gear, handbrake off ( make sure it cant roll !!)

jack up one rear wheel, ensure the other is in full contact with the ground.

IF you can rotate the wheel in the air , then you have an open diff dude

IF it remains static the you have the ultra rare small case LSD fitted, I doubt it though dude, no-one's been that lucky for ages :lol:
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M3Compact
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Post Thu Jul 21, 2005 6:32 pm

I then tried the other technique i was told about; let one side of the car down and tried to spin one wheel, and it did spin,
No LSD mate. :(
Dan318-is
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Post Thu Jul 21, 2005 6:37 pm

darn.
me not happy now!! :(
do 325i diffs fit a 318is?
Karan
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Post Thu Jul 21, 2005 7:08 pm

318-is wrote:darn.
me not happy now!! :(
do 325i diffs fit a 318is?
yep

all u have to do is loosen the prop nut in the centre and slide the rear section of the prop forwrds to accomadate the larger 325 diff
Dan318-is
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Post Thu Jul 21, 2005 7:15 pm

are all 325 standard with a LSD? and is the diff have a LSD built in then? i was under the impression they were seperate units
jmc330i
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Post Thu Jul 21, 2005 8:20 pm

The 325i Sport had the LSD as standard, but it was an option from new, so there will be some 325ise etc with LSDs fitted from the dealer.

The LSD is part of the diff. I guess you can remove the slipper part and fit it to a non LSD, to make an LSD (if you get what I mean).
I dont know how accurate that is, but I was told cause I will be needing a 2.93, 3.15 or 3.25 LSD for my conversion, that I can use an E28 diff and the LSD part from my 3.91diff to make an LSD in the ratio I decide on.
James
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Dan318-is
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Post Thu Jul 21, 2005 8:59 pm

so i can find a LSD of a 325 sport of somehting, preferably in the high 3 ratio's, and cchangeit straight for my current diff an it will work fine?
Simon13
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Post Thu Jul 21, 2005 9:02 pm

yes! u would want a sport diff 3.91 they go for Ԛ£250 and require special LSD oil which is Ԛ£50!

only down side is they are alot heavier than a small case diff
Dan318-is
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Post Thu Jul 21, 2005 9:05 pm

what other options for LSD's do i have apart form 3.91 ??
Ant
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Post Thu Jul 21, 2005 9:22 pm

common is the 3.91, thats closest to the current ratio too dude so would be the weapon of choice

I have a 3.64 LSd in my SE, its a bit too tall for a stock 325 so I would not go there dude

There are 3.73 units about too, rarest ratio for some reason, only ever seen these on 2 cabs and a touring we service @ work

as for swopping the LSD from CWP to CWP, I can see no reason it would not work, the CW bolts to the Planet gears in an open diff so , again in theory the LSD clutch pack would swop.

Not done it mind, dont know anyone that has either.

As for the 330i LSD requirement, one off a 2.8/Z3M coupe would fit that bill, opens up the ratio choices too M8, I'd go for the 2.93(iirc) unit, on paper seems the best match for the box rayios.

Hard to find though, ASC/DSC was more common than LSD 8O
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Dan318-is
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Post Thu Jul 21, 2005 9:41 pm

wow. thanks for that overwhemign amount of info. You know your stuff.

I think im going to save for a 3.91 LSD of a 325i and put it on cos i love sideways, thanks for everyoens advice!
jmc330i
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Post Thu Jul 21, 2005 9:45 pm

ant wrote:As for the 330i LSD requirement, one off a 2.8/Z3M coupe would fit that bill, opens up the ratio choices too M8, I'd go for the 2.93(iirc) unit, on paper seems the best match for the box rayios.
Ive got the E36 M3 5spd box (5th gear 1:1), so an E30 M3 3.25LSD would be good as its close to the original E36 M3 ratio.

I was looking at a 2.93 or 3.07(??) LSD to help bring the revs down at cruising speed, which is where I was told about getting an E28 open diff and fitting my LSD bits to it. Still not sure if this does work and I cant remember where I saw it, but whoever it was seemed certain it would.
James
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'93 318i touring 16v
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Post Fri Jul 22, 2005 2:04 am

Simon13 wrote:yes! u would want a sport diff 3.91 they go for Ԛ£250 and require special LSD oil which is Ԛ£50!
u don't have to use bmw oil, mine has LSD-specific oil of the same visc from a motor factor which was about Ԛ£6/litre if i remember
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