what is the "correct" lsd for a 320i?

[liam012]

I know that correct is not the right term as its not standard on the 320i but i need to know the ratio of lsd to get that wont mess up the final drive of the car - if anyone knows a good place to pick them u too that would be great.
cheers
liam

[Davenotouring]

Keep an eye out on here, and on eBay.

A 3.91 LSD would be fine on a 320i.

You will need to adjust the length of the propshaft though by undoing the centre collar nut because the LSD will be large case and your diff will 95% be small case.

The mounts and everything else is identical.

[liam012]

Cheers dave, can they be got new?

[Giggz]

Sorry to butt in but just curious what is "best" for a 325i then?

[Davenotouring]

You could get one new, but it would be about a grand.

A good second-hand one will be fine.

A 3.64 is good for a 325i, good for the motorway.

A 3.73 is a perfect compromise of acceleration and cruising on a 325i.

A 3.91 is good on a 325i also, best for acceleration, bit buzzy on the motorway, but it's never bothered me.

Hope this helps.

[Giggz]

Thats brilliant.

3.73 sounds like a good compromise like you say.

Stupid question probably...but what do the numbers stand for?

[Davenotouring]

A 3.73 will be hard to come by, but keep an eye out.

The numbers are just the ratios mate.

A 4:1 ratio would mean four turns of the propshaft would create one turn of the wheels. Hence the change in acceleration and revs at motorway speeds of the different ratios.

[Giggz]

OH I SEE.

Thanks for that sir.

While we are on the subject of diffs...would you recommend me changing my diff oil.I ask beacause a mechanic told me not to as my car i so old and i may jeopardise the running of the diff????

[jaistanley]

I have just bought a mega rare (in england anyway) 4.1 big case LSD from an american M3. As my car is a 318is and has very little low down torque I felt a 3.91 would kill the acceleration.

Does a 320i have the grunt for a 3.9. They're specced with a small case open 4.1 like my original diff aren't they?

Jai

[Toby_Unna]

BLATANT ADVERT!!

i have just swapped my 3.91 LSD for a 3.64 LSD

the 3.91 is for sale and it's a good 'un!! perfect for a 320i as Dave says.

http://www.e30zone.co.uk/modules.php?na ... ic&t=16266

Toby

[Davenotouring]

Yeah you should change the oil, but use proper LSD oil, get it from the dealer. You need to take a container there, get two litres.

Tobys diff is a good one, buy it.

A 320i will be fine with a 3.91, mine was.