[M.barnes]

Originally Posted by ska325xi

Its $35k uninstalled, if it was $2k then thats a diff story

Sorry I meant £2k GBP isn't that much, quaife is about the same for the m135i

[M.barnes]

http://www.birdsauto.com/news/bmw-m1...p-differential

[wdlfbio]

Wife drives a '12 Z4 35is foothills east of Seattle. We put blizzaks on it from Nov/Dec - March. No issue in the snow.

[spmd11]

Seems as though many responding here have not owned M cars. An M LSD is amazing and is one of the things that makes an M car so special. You all don't know what you are missing.

In our M3's, in M dynamic mode you can drift in turns with just a touch of power at very modest speeds. It is incredible.

The thing I don't know is how this M performance LSD will compare to an M LSD. If it's as good as an M LSD I would buy it. If not, I would not.

The driving dynamics of an E90/92/93 M is so superior to the non-M cars it's VERY difficult to go back to non LSD BMW product unless you are talking X drive models

[wdlfbio]

She drove an E92 M3 for 50k miles. I have a '12 335 xi. All three are autos. While the M3 certainly out handled either of car, it's really only noticeable on the track, as other have said. Driving it on the street in a manner to routinely feel the difference the LSD of the M offers is probably very irresponsible and illegal. But fun .

[spmd11]

Originally Posted by wdlfbio

Driving it on the street in a manner to routinely feel the difference the LSD of the M offers is probably very irresponsible and illegal. But fun .

Hmmm... I guess I'm in trouble. However, no problem for me to wag the tail just a pinch and still dry responsibly. Just sayin.

No disrespect intended, but if you can't feel the difference of the LSD in normal or slightly spirited driving.. uh.. maybe the M is overkill for you.

[bladeomatic]

Originally Posted by GFK007

3k is steep. I can't justify it because I don't intend to track the car.

Would rather put that money towards an exhaust and a set of 19s.

+1

These items provide benefits for non-track days.

[w3rkn]

1st: The is no reason a nearly $50k performance car doesn't already come with a mechanical LSD.

2nd: The cost (optional) should be supplemented by a $2,500 credit for any BMW, that has a //M in it's name (M135/M235).

3rd: It is not even out yet. I have no doubts it will transform the car, but BMW is feeding off it's customers here.


$50,000+ for a BMW M235i w/lsd ..?
I have a 135is and the car is negative experience/frustrating for not having a LSD. The e-diff is too controlling and nothing is consistent, or constant, as the e-lectonics are always trying to do something different. Now instead of enjoying the finesse of the car, I am fighting it.

So, at nearly $50k (w/lsd), how is the M235is going to touch the new Mustang GT350 (s550)? Or, any other $45,000+ car, that comes standard with a mechanical LSD, or AWD..?

[ska///235i]

ok the argument is that for $3500+ for a lsd is not worth it for the 235

we all already know how good lsd is and how badass the m cars are

Originally Posted by spmd11

Seems as though many responding here have not owned M cars. An M LSD is amazing and is one of the things that makes an M car so special. You all don't know what you are missing.

In our M3's, in M dynamic mode you can drift in turns with just a touch of power at very modest speeds. It is incredible.

The thing I don't know is how this M performance LSD will compare to an M LSD. If it's as good as an M LSD I would buy it. If not, I would not.

The driving dynamics of an E90/92/93 M is so superior to the non-M cars it's VERY difficult to go back to non LSD BMW product unless you are talking X drive models

[Devon K]

Originally Posted by w3rkn

1st: The is no reason a nearly $50k performance car doesn't already come with a mechanical LSD.

.... $50,000+ for a BMW M235i w/lsd ..? ...
So, at nearly $50k (w/lsd), how is the M235is going to touch the new Mustang GT350 (s550)? Or, any other $45,000+ car, that comes standard with a mechanical LSD, or AWD..?

Ridicuous isn't it when you remember that a $26K sportscar (the FRS) comes with one standard....

[jbenderhof]

...and the McLaren P1 has an open diff?

[spmd11]

Originally Posted by w3rkn

1st: The is no reason a nearly $50k performance car doesn't already come with a mechanical LSD.

2nd: The cost (optional) should be supplemented by a $2,500 credit for any BMW, that has a //M in it's name (M135/M235).

3rd: It is not even out yet. I have no doubts it will transform the car, but BMW is feeding off it's customers here.


$50,000+ for a BMW M235i w/lsd ..?
I have a 135is and the car is negative experience/frustrating for not having a LSD. The e-diff is too controlling and nothing is consistent, or constant, as the e-lectonics are always trying to do something different. Now instead of enjoying the finesse of the car, I am fighting it.

FINALLY! Someone said it. +1,000. Thank you for pointing this out!!

[Red Bread]

Originally Posted by jbenderhof

...and the McLaren P1 has an open diff?

Well yes it does, but if you think for a second that BMW has put the kind of development into the brake biased control that Macca has for the P1, I've got a bridge to sell you. Don't forget the rear weight bias of the P1 and the ability to agnostically add e-power to either rear wheel too. However, a great statement by Chris Harris on Pistonheads about the P1's open diff:

I'm the biggest critic of these electronic non-differentials. I think the 12C suffered for not having a mechanical LSD, and even though I do buy all of the engineering arguments that see then as a malign influence in the search for optimum road behaviour, I think modern power outputs require them (and I like doing skids)

The P1's system is the first I've driven that actually works. When you see the video next week, you'll see. The response from the rear axle under power feels like there is a mechanical locking diff. It's uncanny. But I just judge these things on confidence - in a 12C, even in its latest brake-steer calibration ( and late cars are much different to early ones) you never quite know if one or both wheels will spin-up. In the P1, it's always both.

Sounds terrible, but you need to feel it from the cabin to see how it works. For me it was the big question mark over the car's specification, having driven it, it's a compete non-argument.

The perfect suspension system for a RWD car would have no locking rear diff. It corrupts pretty much everything: it effectively adds spring rate under load, it causes understeer,it harms height speed stability in a straight line, and in the case of a plate-type diff it can cause havoc as/when/how it loads and unloads.

But with today's massive power outputs, cars are traction limited and tend to run such stiff springs that the LSD effect is less pronounced because the chassis is already so compromised for road use. And on a practical level, not fitting one to your new super sports car precludes big, controllable slides for the media push. Ask McLaren about that one.

The holy grail I suppose is a constantly variable locking diff that gives 100percent when you need it (post apex) and zero when you don't (braking and turn-in) (the SLS Black has the best one of these I've tried, but BMW M do a good job too)

I don't like stuff with heaps of power/torque and an open diff. It spoils the fun - ergo, I'd sacrifice some Lotus-like compliance to feel that LSD connection between my right foot and the rear axle. This is where those early 12C's struggled. And hence my genuine sense of alarm when I asked C.Goodwin if the car ran an open diff and he smiled and said 'Yes, but drive it before you start shouting at me'.

I'm probably stirring a hornet's nest here, and people with greater knowledge/experience will flame me down, but that's a brief summary of how I view the subject.

Mechanical locking diffs are like a good cigarette: destructive, probably non-justifiable. But in the right circumstances they're perfect and easily justified.

To extent the metaphor: The P1 is the first e-cigarette that could persuade a hardened Marlboro red puffer to go electronic.

[five3three]

Originally Posted by ska325xi

ok the argument is that for $3500+ for a lsd is not worth it for the 235

we all already know how good lsd is and how badass the m cars are

Exactly! My build was close to 51k without an LSD. With the 3600 LSD I'd be at 55k with taxes which puts this car price-wise in territory it shouldn't be in, especially when it should have come standard on the car.

But, for a feature that should be factory installed (or optioned) but isn't and that nobody has even tried/reviewed yet, to shell out that kind of money is not worth it on this car, at least at this point in time.

[grant]

Originally Posted by Spitfi-r

At ~$3k my advice to most of you: "Don't waste your money." If it was $1-2k I might say why not.

I see no point in a LSD on a street driven modern car equipped with DSC etc.

The electronic nannies will kick in as soon as you have wheel slip. In low traction situations like snow you are better off leaving all that stuff on as it'll do a better job as a whole than just a mechanical LSD.

Even for a track driven car with the DSC etc turned off it would be rare to have wheel spin on anything but the tightest turns driven at 10/10ths.

With some stiff springs and a stiff roll bar the LSD would help you put power down during autocross or if burnouts and drifting are you thing then the LSD will obviously help.


My background:
~2500lb track e30 with ~280 HP on 205 series tires
Tracked 2001 330 open diff

I absolutely disagree. If I could only have one option on the car, it would be LSD (and I have 12 years of track experience with a wide variety of vehicles and I live in Denver with plenty of opportunites to drive in low-friciton conditions on the road).

I would guess than your E30 did not have 330 ft-lbs of torque from 1,400 rpm?

[spmd11]

Originally Posted by ska325xi

ok the argument is that for $3500+ for a lsd is not worth it for the 235

we all already know how good lsd is and how badass the m cars are

Point taken.

[Greenkirby21]

Does anyone know what kind of LSD it is? There are many different types of LSD qualities. Also, anyone know if the gear ratios change or anything?

For example, turner sells some LSD that are 2,000 for the parts alone. With installation, you could probabaly get into the 3K range and it's not OEM or backed up BMW warranty

[Red Bread]

Of all the parts you could change on a car that influence warranty claims, I'd think an LSD would be somewhere between lug nuts and the little button on the end of the e-brake handle.

[Spitfi-r]

Originally Posted by grant

I absolutely disagree. If I could only have one option on the car, it would be LSD (and I have 12 years of track experience with a wide variety of vehicles and I live in Denver with plenty of opportunites to drive in low-friciton conditions on the road).

I would guess than your E30 did not have 330 ft-lbs of torque from 1,400 rpm?

Do you disagree for yourself or for most m235i buyers?
You have 12 years of track experience and could definitely benefit from the LSD.
Only a small portion of m235i's will ever see track time, and even fewer will be driven in a competition where the fraction of a second gained from a LSD will matter.

I still don't see the need for it on the street if the nannies are on.

P.S. My E30 is NA, so the torque comes in way past 1,400.
P.P.S. I bet your 911 is a beast!

[grant]

Originally Posted by Spitfi-r

Do you disagree for yourself or for most m235i buyers?
You have 12 years of track experience and could definitely benefit from the LSD.
Only a small portion of m235i's will ever see track time, and even fewer will be driven in a competition where the fraction of a second gained from a LSD will matter.

I still don't see the need for it on the street if the nannies are on.

P.S. My E30 is NA, so the torque comes in way past 1,400.
P.P.S. I bet your 911 is a beast!

Wouldn't want one for the laptime improvement - just to save myself from the incredible frustration that comes from electronic nannies applying the brakes to a spinning wheel with dsc on or lack of forward motivation with dsc off. This applies to both road and track.

I would assume that generally enthusiast drivers are the target market for this car, so it applies to us all.

[ska///235i]

Again....is it worth the $3500+

[Bee Pee]

Hi all

Just had quaife LSD, birds b1 ARBs and H&R sport springs put on my m135i with oem adaptive damper

Superb

All for about the same price installed as an oem drexler LSD retrofit would be from BMW.

Happy days

Originally Posted by M.barnes

http://www.birdsauto.com/news/bmw-m1...p-differential