If BMW doesnt put LSD (limit slip diff) in 135i, would aftermarket LSD void warranty?

[GoingTooFast]

«Suited for all engines and drivetrains.»

So they say...:smile:

[Powerman]

Originally Posted by GoingTooFast

«Suited for all engines and drivetrains.»

So they say...:smile:

But it seems like they are talking about a new addition to X-drive. Not some new slick LSD they are putting in other platforms.

[GoingTooFast]

So, you think a performance oriented veichle such as the 135i wouldn't benefit from that system as much as, say, a ###Xi to the point of BMW having two different systems, one being clearly better than the other?!

I take my bet on...

[atr_hugo]

It'll be interesting to see which system they use on the 135i diff. When the initial info came out on the car it sounded like the car would come with an open diff and utilize the ABS software to compensate for wheelspin. I'm hoping we get that diff you showed us.

[GoingTooFast]

Originally Posted by atr_hugo

... When the initial info came out on the car it sounded like the car would come with an open diff and utilize the ABS software to compensate for wheelspin.

Why do you say that?!

Let's take the following sentence from the 135i press release about the "Electronic rear differential lock":

«Active when DCS completely swithced off»


Now, let's see what the link I've just posted says (page 2):

«Since, as a result, DSC Dynamic Stability Control is not required so often to give the driver additional safety and protection, a further advantage of Dynamic Performance Control is that the driver benefits from the full power of the engine under most driving conditions.»


«Rather, the primary objective from the beginning was to improve driving safety, agility and nimble performance, as well as driving pleasure as such, particularly under everyday driving conditions. Hence, the less routined motorist will also benefit from all these advantages as soon as Dynamic Performance Control is introduced in series production. The bottom line, therefore, is that Dynamic Performance Control offers even greater safety reserves by providing greater stability.»


Now you can sue BMW for not providing all the safety mechanisms they have without proper warning if they wouldn't use the "Dynamic Performance Control" in the 135i...

[atr_hugo]

Methinks you're parsing the words too finely - we'll have to wait and see what it really is. Again, I hope you're right, but the cynic in me says they're taking the easy way out and using the ABS circuitry.

[GoingTooFast]

Believe me... in Europe a BMW 135i is NOT cheap at all!!!

[atr_hugo]

Yuop - we've seen the pricing. Oh and I just edited the word 'cheap' to read 'easy' for those of you wondering about GoingTooFast's response.

[Advevo]

I bet ya that s not the diff which is going into a 135i. It s too big and heavy for such a small car.

We get a normal diff with a wealded crownwheel so no one puts in a lsd. And the simulation is done by the abs which detect slip and brakes the wheel which has wheelspin.

[GoingTooFast]

Originally Posted by Advevo

I bet ya that s not the diff which is going into a 135i. It s too big and heavy for such a small car.

How can you tell how much weight can an additional planetary gear set and a pair of electronically controlled multi-plate clutches add to the differential?!

It all depends on the size of the original differential...

Besides, I thought you were the one who said that the 135i already weighted like a pig... maybe there's an explanation after all...




«With Dynamic Performance Control, up to 1800 Newton meters of force can be distributed among the rear wheels in fractions of a second. This BMW innovation makes higher lateral accelerations possible and enables sportier acceleration out of a curve. It also makes driving simultaneously safer and more dynamic-even for vehicles without four-wheel drive.

Development of Dynamic Performance Control is not yet complete. Combined with an integrated chassis management system and BMW Active Front Steering, additional safety, comfort and convenience functions can be implemented before the first production phase-in. During their three to six-month familiarisation period, new BMW Group Chassis Development employees explore a wide variety of interesting technical issues.»

BMW Group (Issue 03/2007)



Let's just say that the DPC wil be available at the beginning of 2008...:roundel:

[Advevo]

yes the 135i weight is like a pig compared to a 130i it s 110kg heavier and that s a lot.

My wait is for an M1 with a proper diff and i am no turbo driver either.

[kurichan]

Originally Posted by mikeo

Guys, on a true open differential once one wheel spins ALL the torque goes to that spinning wheel, with effectively no drive force being transmitted to the other wheel. It follows that if the EDL applies the brake to the spinning wheel, a significant percentage of the torque MUST be sent to the non-spinning wheel.

+1 - You're saying what I tried to say more eloquently!

[GoingTooFast]

Originally Posted by Advevo

yes the 135i weight is like a pig compared to a 130i it s 110kg heavier and that s a lot.

I agree with you... too much weight!

Originally Posted by Advevo

My wait is for an M1 with a proper diff and i am no turbo driver either.

It's more likely to have the DPC installed on the 135i than an M1 version ever being released...

I think your driving style get along with turbo also... because turbo equals torque at the rear wheels... which means... drifting paradise!!!:thumbup:

[qaz393]

get a hartge complete lsd and you will be good

[Powerman]

I'm willing to bet that that diff is not what BMW is talking about in the 135i. I think that is an addition to x-drive and BMW will not be putting that in RWD vehicles for some time. That is an an actuall electronicly actuated mechanical LSD. To put one in RWDs would be a departure from BMW's policy of LSDs in M-power cars only. I would tend to believe they would be making a bigger deal out of that in the 135i than the little blurb they mentioned in their product info.

I have no doubt that what was posted is indeed a new take on a LSD that would be better than open. I don't doubt that the electronic wheel braking scheme will be better than an open diff only. I also don't believe either setup is on par with actuall LSDs put in M-cars, or aftermarket LSDs. 1800nm is a mild LSD. Just using gear ratios for a 6 speed MT for the 335i, you are getting ~4000 ft/lbs. of torque to the half shafts in first gear. So 1800nm is less than half the torque going to one wheel.

[gotgemini2000]

What bothers me about the lack of the LSD more than anything is just that it would be so easy and cheap for them to put it in the car. Yes, I understand that BMW is running on extremely narrow margins, especially with the Euro/Dollar exchange rates, but I would gladly pay 2,000 dollars for a BMW LSD on my 135i. It seems like BMW is deliberately making the 135i worse then it could potentially be only for the sake of marketing.

[gemini330zhp]

Originally Posted by GoingTooFast

Correct!



Wrong!



Maybe this is because after March 2007 the 335i got the Dynamic Performance Control diff. (aka E-LSD)which is a mechatronic system where the final drive is combined with two superimposed gearsets and two electronically controlled multiple-plate brakes (one for each wheel):





So, it's NOT your rear pads that may wear-off but these multiple-plate brakes on the differential itself, just like the multiple clutch plates do in a normal LSD.

All the ABS system do is providing the sensors for detecting wheel spin.

The mechatronic system takes up to 100 milliseconds for generating the maximum breaking force. And, regardless of the drive power generated by the engine the maximum difference in forces between the left- and right-hand rear wheel which can be built up by the system is 1,800 Nm. This defines your percentage of locking.

This setup also means that at NO engine torque (with the clutch disengaged for instance) you still benefit from the locking effect as opposed to what would happened with a mechanical LSD where you were basically driving with an open diff.

See its a new thing and looks promising I like the concept probally works very well!!!! Like I said we have to wait and see how it works on the 135i!!! The 335i guys are doing well so lets see!!!

[Powerman]

Originally Posted by GoingTooFast

Maybe this is because after March 2007 the 335i got the Dynamic Performance Control diff. (aka E-LSD)which is a mechatronic system where the final drive is combined with two superimposed gearsets and two electronically controlled multiple-plate brakes (one for each wheel):

I missed this the first time. Please excuse me, I'm a little OCD. I don't mean to be a butt head about this.:wink:

No where on BMW's site can I find this in any 335. Not even the x-drive. Nor an any other vehicle. It is not out yet. Googling for more information netted me this article dated April 07:

BMW has just taken the wraps off an advanced torque vectoring system that promises to improve both the agility and stability of its four-wheel drive models.
Called Dynamic Performance Control, the new system is an evolution of BMW’s xDrive system, but adds a series of additional electro-magnetic clutches, in a modified rear differential housing that allow power to be juggled between the individual rear wheels as well as between the front and rear axles.
Dynamic Performance Control works in conjunction with sensors in the anti-lock braking system that measure steering angle, yaw rates, road speed and torque developed by the engine. Essentially, it directs drive to where it can be used most effectively in an operation not dissimilar to that of a traditional locking differential on a rear-wheel-drive car.
If the car understeers, xDrive will redirect more drive to the rear wheels and, if required, the Dynamic Performance Control system will then load up the outside rear wheel with the balance of power, providing an additional turning moment beyond that generated by the steering wheels. During oversteer, it reverses the action, sending the majority of drive through the front wheels and, if necessary, increasing torque to the inside rear wheel to stabilise the car during cornering. Both processes are explained in BMW's images, which you'll find in our gallery.
Unlike similar systems developed by rival car makers, BMW’s Dynamic Performance Control operates both under load and on the overrun, meaning the car continues to be stabilised even when the driver steps off the throttle mid-corner. The new system adds 12kg to the weight of the car, but it is concentrated low down in the chassis so as not to affect handling to any great degree.

Coming to a BMW near you


BMW is tight-lipped on when Dynamic Performance Control, developed in partnership with German engineering specialist ZF, will be introduced. It will probably appear first on the X6 crossover coupe, before heading into other models, including the X3, X5 and four-wheel-drive versions of the 3-, 5- and next-generation 7-series. Also earmarked to accept the new system is BMW’s seven-seat MPV, and a secret new junior four-wheel-drive that’s tipped to slot into the German car maker’s line-up beneath the X3.

They go on to talk about how it feels

http://www.autocarmagazine.co.uk/New...llCars/225098/

With so many different lables of traction control systems, it is easy to mix them all up. All I found on the 335 is the "Dynamic Stability Control", and the "Dynamic Traction Control" brake management system. I guess I would have to go over to other forums to find out what owners think of it. However, the new diff by BMW is not in the 335s and is not going to be in the 135i any time soon. This is an enhanced x-drive component to compete with Quattro, 4 matic and the like. It does sound like a good deal in the 335xi though. When that will happen has not been announced.

[larryn]

Powerman, that's what I said earlier when the question was posed.

I keep up with posts/news on the e90/e92 , since I have one. I had not heard of that new EDL setup until they announced it for 135i. I don't follow news on the X series, so I assumed this was in place already, based on GoingTooFast's posts.

[Powerman]

Originally Posted by larryn

Powerman, that's what I said earlier when the question was posed.

I keep up with posts/news on the e90/e92 , since I have one. I had not heard of that new EDL setup until they announced it for 135i. I don't follow news on the X series, so I assumed this was in place already, based on GoingTooFast's posts.

Well there is a ton of misinformation out there. Many, many discussions that are identical to this one. They all talk about the wheel brake scheme, then they call it a imitation electronic LSD, then they talk about THE electronic LSD being introduced in the 135i.:iono:

I could certainly be on the wrong side of the argument. One thing that was mentioned is it is biased at 40%. So that at least coincides with my numbers I had. As I mentioned, that is not very aggressive. With other clutch types doing 60% and others still being variable. However, it might be good enough for most cases to forgo shelling out a fair bit for a new after market one. Meaning that would be a lot of money for the small difference over the E-LSD.

As with everything at this point, all we can do is guess, and wait, and guess some more, and wait.....and devour any minuscule piece of info like it was crack.

[larryn]

Originally Posted by Powerman

.....and devour any minuscule piece of info like it was crack.

think they'll give us out first taste for free?

Btw, all past BMW LSDs that I know of, other than the recent M specific ones, have a 40% lockup. So, IF the E-LSD has a 40% lockup as well, it could be similar in effect to those. Again, who the freak knows at this point. Lets just drink lots and sleep longer to make the time fly by until more info with reviews are released.

[Powerman]

Originally Posted by larryn

think they'll give us out first taste for free?

Btw, all past BMW LSDs that I know of, other than the recent M specific ones, have a 40% lockup.

I'm a noob to BMW so I didn't know that about 40%. I know LSDs for off road and 50%-60% is not uncommon so that is why I said that.

Wake me when it's over and take me to detox:drinking: