E30 Zone

Hi, new member here so my first post. Question is, do all 325i's have an limited slip diff ? If not, are they readily available and relatively straight forward to fit ?

Thanks

No, quite, yes.

an option on all but 325 sports iirc. easily changed as a direct swap

LSD was always an option. Once our new zone is running(some time next week I think) we will have a proper classified adds section to search for morsels like this.Expect to pay around £250. Held in by the driveshafts and 5 bolts.The top 4 are fiddly to reach and the diff is heavy so a decent jack is needed to lift/lower.Whilst the diff is on the floor it would be sensible to replace it's rear bush with either a Z3M item or a polybush one.

Only the 325i sports had them as standard.

There are 3 common ratio LSD's for 325i's and they are...

3.91 (the most common)
3.73 (the least common and most popular as its in the middle of the other two)
3.64

I have a 3.73 ratio LSD for sale for £300

I ALSO HAVE ONE AND YOU CAN HAVE IT FOR £250

andy1200 wrote:I ALSO HAVE ONE AND YOU CAN HAVE IT FOR £250

3.73?!

Thanks may well be interested in buying one off you but I haven't yet got a car, probably getting one tomorrow and I'm unsure if it has one fitted yet.

So got a car now, 325i Touring. What's the quickest way of seeing if it has an LSD fitted ? Any features on the diff casing that tells the two types of diff apart ?

Read zone wiki section. Link at the top of the page.

Thanks mate, keep forgetting to check the Wiki's.

wixer wrote:So got a car now, 325i Touring. What's the quickest way of seeing if it has an LSD fitted ?

do a monumental wheelspin,if you leave 2 long stripes its a slipper!

bss325i wrote:

andy1200 wrote:I ALSO HAVE ONE AND YOU CAN HAVE IT FOR £250

3.73?!

its proberbly a 4.1 open diff barry lmao!

leeparkes wrote:

wixer wrote:So got a car now, 325i Touring. What's the quickest way of seeing if it has an LSD fitted ?

do a monumental wheelspin,if you leave 2 long stripes its a slipper!

Can be inconclusive

A mate tried it with his I.S and figured it had a slipper
2 mins later after i'd jacked up the rear.I proved it didn't.

Jack up 1 side of the car,and with the h/brake off and gearbox in neutral If you can spin the wheel that's in the air it's not a slipper
If you can't spin the wheel, then it's a slipper

Some LSD's are so poor that they nearly become open! Check to see how well you can pull away with one wheel on the grass and one on tarmac.

Whilst on the subject of BMW LSD's, does the same 25% lock apply for on power and also coasting?

A standard LSD I presume allows 75% of slip when on the throttle and also 75% of slip when costing. Is that right?

Some diffs that are used in motorsport in RWD cars use different ramp rates to allow for differing lock up on throttle and coast, allowing for better drive(harsher lock up) on acceleration and less understeer into corners(less lock up, or more slip) on coast.

Quite common is 50/85 IIRC allowing for 50 lock up on Accel, and only 15% lock on coast to minimise understeer into a corner.

Could a Bmw LSD be developed to do this, or is it custom job time due to the design of BMW diffs? Kazz or TranX spring to mind.

Jon_Bmw wrote:Some LSD's are so poor that they nearly become open! Check to see how well you can pull away with one wheel on the grass and one on tarmac.

Whilst on the subject of BMW LSD's, does the same 25% lock apply for on power and also coasting?

A standard LSD I presume allows 75% of slip when on the throttle and also 75% of slip when costing. Is that right?

Some diffs that are used in motorsport in RWD cars use different ramp rates to allow for differing lock up on throttle and coast, allowing for better drive(harsher lock up) on acceleration and less understeer into corners(less lock up, or more slip) on coast.

Quite common is 50/85 IIRC allowing for 50 lock up on Accel, and only 15% lock on coast to minimise understeer into a corner.

Could a Bmw LSD be developed to do this, or is it custom job time due to the design of BMW diffs? Kazz or TranX spring to mind.

Welder FTW!!

Jon_Bmw wrote: Could a Bmw LSD be developed to do this, or is it custom job time due to the design of BMW diffs? Kazz or TranX spring to mind.

Just need to modify the ramp IIRC


Kevo should be able to confirm

Lol Jhonno! I have never looked in the e30 diff, and tbh I am not too sure how they work without looking at one. But can you change the accel ramp, and have a different coast ramp? Thats my question I guess, kevo?

Bump.