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      07-19-2012, 05:37 PM   #67
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Now whose being insulting?
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      07-19-2012, 05:51 PM   #68
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Quote:
Originally Posted by BrokenVert View Post
Now whose being insulting?


Sorry, it was not my intention to be insulting.
I apologize if I came across as such.

Let me reply more sincere:
No, there is nothing in that video that would lead me to believe that the electronic diff is behaving in any detracting manner. Also, there's absolutely nothing in the video that would make me believe the driver would be better off with a completely open diff. That being the motivation for me to make this thread in the first place.
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      07-19-2012, 11:39 PM   #69
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Great write up int2str! Thank you for the information

I'm surprised there isn't much support for this information. People need to chill
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      07-20-2012, 04:04 AM   #70
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Quote:
Originally Posted by int2str View Post


Sorry, it was not my intention to be insulting.
I apologize if I came across as such.

Let me reply more sincere:
No, there is nothing in that video that would lead me to believe that the electronic diff is behaving in any detracting manner. Also, there's absolutely nothing in the video that would make me believe the driver would be better off with a completely open diff. That being the motivation for me to make this thread in the first place.

Really? How is laughing at way I said and offering now other response not meant to be insulting?

Firstly - we must be watching two differen videos

Secondly - I said nothing about an open diff, where did that come from?
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      07-20-2012, 04:19 AM   #71
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The e-diff can't do this

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      07-20-2012, 04:31 AM   #72
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Quote:
Originally Posted by BrokenVert View Post
Really? How is laughing at way I said and offering now other response not meant to be insulting?
Sorry, tired of arguing with you.

Quote:
Firstly - we must be watching two differen videos
Apparently.

Quote:
Secondly - I said nothing about an open diff, where did that come from?
4 pages in and you're still not getting the point of this thread. Also not reading what I wrote. I won't repeat myself again.
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      07-20-2012, 04:55 AM   #73
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Quote:
Originally Posted by int2str View Post
4 pages in and you're still not getting the point of this thread. Also not reading what I wrote. I won't repeat myself again.
The point of this thread was for you to share information that you researched. I understand that perfectly.

But then it became the merits of LSD vs eLSD - and that's what I'm comparing. The only one mentioning open diff is you. And honestly it's a moot point because anything is better than an open diff.


This was never an argument. It was a discussion. If you thought otherwise I apologise.
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      07-20-2012, 05:10 AM   #74
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Quote:
Originally Posted by int2str View Post
Sorry, tired of arguing with you.



Apparently.



4 pages in and you're still not getting the point of this thread. Also not reading what I wrote. I won't repeat myself again.
Relax buddy all I said was...

Quote:
Originally Posted by BMW86 View Post
The e-diff can't do this

Correct me if I'm wrong?
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      07-20-2012, 05:16 AM   #75
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Quote:
Originally Posted by BMW86 View Post
Relax buddy all I said was...
Correct me if I'm wrong?
I wasn't talking to you.
And yes, you're wrong.
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      07-20-2012, 05:25 AM   #76
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Quote:
Originally Posted by BrokenVert View Post
But then it became the merits of LSD vs eLSD - and that's what I'm comparing.
That's for another thread.

Quote:
The only one mentioning open diff is you. And honestly it's a moot point because anything is better than an open diff.
Good, another thing we agree on.
I'd love to keep discussing eDiff vs. LSD, I just don't want other people to think that just because LSD is better, eDiff is useless or dangerous.

You already know where I stand on eDiff vs. LSD - I bought a Quaife myself. But if I wasn't competing in autocrosses, I would have been very happy to save the money since eDiff gets you mostly there.

Let me try to clarify the point about your pulsing/notchiness argument and clarify what I mean about the video:
First of, the eLSD doesn't pulse anything. Attached is another graph for you. The bottom, blue lines show the differential braking of the inside wheel. Notice how little the brakes are applied (compare it to me actually braking for the next turn) and how gradual and steady the brakes are applied. You can see though that the wheel speed balance is somewhat upset though (center charts), but the explanation is not the diff - it's the driver. Look at my sloppy throttle input (top chart).

This brings me to your comments on the video:
"See how it came out in steps and not one progressive slide? Thats the notchy action of the eLSD that I was talking about. It even tried to bite him back twice"

I see no evidence of this at all in the video. The data I've been able to collect from my own car also does not corroborate this.
Have you considered that the driver in the video is simply making corrections to keep the car on the narrow on-ramp? Did you watch the 2nd video where the same driver in the same car drifts nice and smooth in a less dangerous environment?

Also, I never argued that LSD isn't better for smoother control and confidence...
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      07-20-2012, 05:45 AM   #77
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Quote:
Originally Posted by int2str View Post
I wasn't talking to you.
And yes, you're wrong.
My mistake! long day
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      07-21-2012, 08:03 PM   #78
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ediff on my car must be broken because in tight autocross conditions it's a one wheel wonder
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      07-21-2012, 09:26 PM   #79
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I know this is probably a stupid question, but how is this different than DSC/DTC? Don't they both apply the brakes to the wheel with the least amount grip?
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      07-21-2012, 09:52 PM   #80
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Quote:
Originally Posted by imported_mega View Post
ediff on my car must be broken because in tight autocross conditions it's a one wheel wonder
Yes, either it's broken (doubt it) or your perception of it is off.
Here's a pre-LSD autocross of mine. Note that both wheels are spinning and drawing lines on the pavement.


And no, the spin had nothing to do with the differential - I made the mistake of lifting right as the weight transfer happened... doh.

Quote:
Originally Posted by bimmerjph View Post
I know this is probably a stupid question, but how is this different than DSC/DTC? Don't they both apply the brakes to the wheel with the least amount grip?
DSC and to an extend DTC try to prevent wheel-spin. Both cut power and intervene heavily to keep you on the road. Adaptive differential braking only tries to put power to both wheels. Also you can't turn the eDiff off.
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      07-22-2012, 03:30 AM   #81
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Great thread. Very educational for me. Didn't know anything about how lsd worked before reading all the stuff here.

If I understand correctly, a significant difference between eLSD and LSD is that with eLSD torque is never transferred from one wheel to the other as is the case with LSD. eLSD uses open diff which by design splits torque 50-50 between the two wheels all the time. Therefore when the eLSD system controls slippage by braking, it results in pure loss of energy. Whereas, an LSD controls slippage by transferring power between the two wheel.

I believe this is what a number of earlier poster already eluded to. Just wanted to provide a bit more clarity on the mechanical aspect.

Apologies if what I said here is wrong or redundant. I got the info from wikipedia and other articles on the web.

Cheers.
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      07-22-2012, 06:21 AM   #82
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Quote:
Originally Posted by int2str View Post
Yes, either it's broken (doubt it) or your perception of it is off.
I went from e30's with LSD's and an m3 to my 135i, the difference in the rear end is drastic, I got used to it, but it sure is NOT an LSD

sandy stop signs are this car's weakness
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      07-22-2012, 06:49 AM   #83
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At the risk of repeating myself, there are a lot of BMW owners spending money on all sorts of mods, but except for the drag racers, I don't see before and after track times posted. Somewhere, I recall, in this thread someone backed in to the subjective "feel is so important" corner. They may stay there.
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      07-22-2012, 09:26 AM   #84
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Quote:
Originally Posted by mike649 View Post
If I understand correctly, a significant difference between eLSD and LSD is that with eLSD torque is never transferred from one wheel to the other as is the case with LSD. eLSD uses open diff which by design splits torque 50-50 between the two wheels all the time. Therefore when the eLSD system controls slippage by braking, it results in pure loss of energy. Whereas, an LSD controls slippage by transferring power between the two wheel.
Applying brake force to one wheel on an open diff does actually transfer torque to the other wheel. The real point is to keep any given wheel from spinning freely, which can actually just raise engine RPM without increasing vehicle speed. When a wheel spins you waste some energy just accelerating the engine and drivetrain components.

Yes, some energy is lost as heat in the brakes, but it's not 100% loss in the way you are thinking.
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      07-22-2012, 09:56 AM   #85
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Quote:
Originally Posted by Diver View Post
At the risk of repeating myself, there are a lot of BMW owners spending money on all sorts of mods, but except for the drag racers, I don't see before and after track times posted. Somewhere, I recall, in this thread someone backed in to the subjective "feel is so important" corner. They may stay there.
Feel leads to confidence which leads to better lap times. Why isn't that just as important as raw numbers?

Also I don't have a real LSD on my car. Perhaps those who do have them - like the OP - can comment in more detail
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      07-22-2012, 10:08 AM   #86
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Quote:
Originally Posted by BrokenVert View Post
Feel leads to confidence which leads to better lap times. Why isn't that just as important as raw numbers?

Also I don't have a real LSD on my car. Perhaps those who do have them - like the OP - can comment in more detail
I dont see it making a difference on race track lap times, where the turns are not so sharp and are high speed

but autocross where you have hairpin turns, low gears and a lotta torque hitting the ground, it absolutely will make a difference, anyone that's autocrossed both can tell you this
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      07-22-2012, 10:14 AM   #87
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Quote:
Originally Posted by imported_mega View Post
I dont see it making a difference on race track lap times, where the turns are not so sharp and are high speed

but autocross where you have hairpin turns, low gears and a lotta torque hitting the ground, it absolutely will make a difference, anyone that's autocrossed both can tell you this
Jensen Button would beg to differ on your first paragraph.

A few races ago he switched to hamiltons exact setup - and up until this past weekend he barely made it into Q3 - unlike hammy who nailed it close to pole every time.

Feel is more important than you make it out to be.
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      07-22-2012, 10:16 AM   #88
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Quote:
Originally Posted by BrokenVert View Post
Feel is more important than you make it out to be.
what? I said they feel completely different

my biggest complaint about my 135 is the open diff
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