How rare are 4.10 LSD

Tue Apr 17, 2007 4:43 pm

Does anyone have any idea of how many 318is came out with a 4.10 LSD?
Also I have heard that the US M3 had a 4.10 LSD. Is this a straight swap into an is?

Mick

Tue Apr 17, 2007 4:44 pm

Rare as rocking horse poo is the answer.

Tue Apr 17, 2007 5:07 pm

I was told about 2/3 of European iS were fitted with the LSD but hardly any in the UK. No stats available that I have seen but I am sure one could get the data out of the Dealer VIN database thingy to find out, just a matter of BMW giving you access.

I imagine M3 diff will not fit an iS, plus sounds like quite a high ratio for an M3 I would have thought it would be more like 3.14 or 3.64.

Tue Apr 17, 2007 5:38 pm

yep too high for m3 afaik m3's came with the 3.15 or something around that

Tue Apr 17, 2007 5:40 pm

There's one for sale at the moment on egay.com

Bit of a shitter that hardly none of the uk cars came with them

Pal

Tue Apr 17, 2007 5:42 pm

M3s in america came with 4.2s as they didn't have dogleg boxes

The uk/eurpean cars came with 3.25 with a couple of exceptions

Wed Apr 18, 2007 10:17 am

I have one off a m3 e30. Will be for sale very soon!!!

Being rebuilt this week!

Wed Apr 18, 2007 10:49 am

I also have 'medium' (large E30) one from an american M3. I thought it's a 4.1 rather than a 4.2? Fitting it, the ratios are exactly the same as my original 318iS open diff.

I'm currently running it in the iS but with a M20B25. Haven't had a chance to drive it much but it's flipping pokey! I'm considering selling the 4.1 and fitting a 3.64 or something for better fuel economy so mine might be for sale too. I need to give Dan first refusal though, I said I would ages back.

Jai

Wed Apr 18, 2007 11:35 am

jaistanley wrote:I also have 'medium' (large E30) one from an american M3. I thought it's a 4.1 rather than a 4.2? Fitting it, the ratios are exactly the same as my original 318iS open diff.

I'm currently running it in the iS but with a M20B25. Haven't had a chance to drive it much but it's flipping pokey! I'm considering selling the 4.1 and fitting a 3.64 or something for better fuel economy so mine might be for sale too. I need to give Dan first refusal though, I said I would ages back.

Jai

I'll have 2nd dibs then pls Jai, on that lsd mate...What's the exact ratio??

Pal

Wed Apr 18, 2007 4:59 pm

wouldnt that LSD give a lower top end but lightning acceleration?

Wed Apr 18, 2007 5:01 pm

4.2, yes - lower top end and quicker acceleration but by bugger all from a 4.1!

Wed Apr 18, 2007 5:13 pm

Flipping 'ell.. 4.2 all this time!

You live and learn.

Jai

Wed Apr 18, 2007 5:16 pm

My mates got a 4.1 lsd in his Alpina C2! No wonder i could never catch him!

Thu Apr 19, 2007 1:42 am

US spec M3 came with a 4.1 LSD, regular UK end euro M3's came with 3.25, evo had a 3.15 ( large case by e30 standards)

many other ratios available as well, and even higher 4.27 and 4.45 ( large case again) though are not realy suited to raod driving, even a 4.1 will be crap on a 325i on the road, too thrashy and for every changing gear!

Thu Apr 19, 2007 1:54 am

jaistanley wrote:I also have 'medium' (large E30) one from an american M3. I thought it's a 4.1 rather than a 4.2? Fitting it, the ratios are exactly the same as my original 318iS open diff.

I'm currently running it in the iS but with a M20B25. Haven't had a chance to drive it much but it's flipping pokey! I'm considering selling the 4.1 and fitting a 3.64 or something for better fuel economy so mine might be for sale too. I need to give Dan first refusal though, I said I would ages back.

Jai

Jai i have acquired a 4.27 LSD for now which suits me down to the ground (short gearing

) thanks for remembering me though!

Kos wrote:, and even higher 4.27 and 4.45 ( large case again) though are not realy suited to raod driving, even a 4.1 will be crap on a 325i on the road, too thrashy and for every changing gear!

says who

Thu Apr 19, 2007 2:12 am

Dan318-is wrote:
Kos wrote:, and even higher 4.27 and 4.45 ( large case again) though are not realy suited to raod driving, even a 4.1 will be crap on a 325i on the road, too thrashy and for every changing gear!
says who

be realistic dan, i'll give you an example

high powered 325i be it turbo or good 2.7 etc with a 4.1 being timed to 100 mph, short diff, more gear changes = lost time, now if you run the same car on a 3.73 it will pull harder through the gears, and keep it in the power band for longer, do you follow ?

Thu Apr 19, 2007 9:42 am

Kos wrote:
Dan318-is wrote:
Kos wrote:, and even higher 4.27 and 4.45 ( large case again) though are not realy suited to raod driving, even a 4.1 will be crap on a 325i on the road, too thrashy and for every changing gear!
says who
be realistic dan, i'll give you an example

high powered 325i be it turbo or good 2.7 etc with a 4.1 being timed to 100 mph, short diff, more gear changes = lost time, now if you run the same car on a 3.73 it will pull harder through the gears, and keep it in the power band for longer, do you follow ?

IMHO that example is wrong. The whole point in fitting a higher ratio diff is to lower the gearing and increase the acceleration.

Im not the only one who thinks this either!

http://www.e30eta.com/ecdiff.htm

Thu Apr 19, 2007 10:07 am

I also have 'medium' (large E30) one from an american M3. I thought it's a 4.1 rather than a 4.2? Fitting it, the ratios are exactly the same as my original 318iS open diff.

I'm currently running it in the iS but with a M20B25. Haven't had a chance to drive it much but it's flipping pokey! I'm considering selling the 4.1 and fitting a 3.64 or something for better fuel economy so mine might be for sale too. I need to give Dan first refusal though, I said I would ages back.

Jai

I have one off a m3 e30. Will be for sale very soon!!!

Being rebuilt this week!

If either of you are selling please warn me I have a wanted up but don't fancy my chances

Thu Apr 19, 2007 10:27 am

I am after one as well, reason I started this thread. If anyone wants to sell one please let me know.