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      04-05-2013, 02:34 AM   #23
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Quote:
Originally Posted by admranger View Post
Wow, crazy pad wear given the Endless' reputation for long life. Wow.

Great stuff.

Soooooo, how hard is it to code the euro MDM into the car?
Next time you're in LA or OC, it can be done for $60, and that includes anything else you want coded; like the Accept screen delete, folding mirrors with the door handle or key fob or anything else you may want. It's a flat rate. I haven't checked out the Vegas forums to see if anyone does it there.

Of if you have the time and know computers: bmw coding(one word) dot com

.

And that Nascar 1/2 at AAA definitely gives the regular MDM fits... which makes the rear end wiggle . I haven't tried with Euro MDM yet.

.
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Let me get this straight... You are swapping out parts designed by some of the top engineers in the world because some guys sponsored by a company told you it's "better??" But when you ask the same guy about tracking, "oh no, I have a kid now" or "I just detailed my car." or "i just got new tires."

Last edited by aus; 04-05-2013 at 02:43 AM..
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      04-05-2013, 11:45 AM   #24
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Quote:
Originally Posted by Ti-Jean View Post
I have KW clubsport suspension with stock swaybars.

I'm always trying to get a picture with a wheel lifted but it seems pretty hard to get. Your theory is still possible though.
The wheel doesn't have to come fully off the track surface for MDM to intervene, IMO. It just needs to be unloaded enough to *almost* spin freely.

I'd set up another camera pointed at the left front wheel, if you're coming to Auto Club Speedway on May 3rd, to see if it's intervening when it's lifting. Set the camera nice and low, on the sideskirt low enough to capture the wheel's hop and see if it brakes when the tire lifts off the ground.
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      04-05-2013, 11:55 AM   #25
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Quote:
Originally Posted by The HACK View Post
The wheel doesn't have to come fully off the track surface for MDM to intervene, IMO. It just needs to be unloaded enough to *almost* spin freely.

I'd set up another camera pointed at the left front wheel, if you're coming to Auto Club Speedway on May 3rd, to see if it's intervening when it's lifting. Set the camera nice and low, on the sideskirt low enough to capture the wheel's hop and see if it brakes when the tire lifts off the ground.
I am not sure front wheel lift is what is causing MDM intervention. Watching the video, most of the time it is the front/outside wheel that is being braked. This is consistent with a stability system wanting to correct/prevent and oversteer condition. IMO, a front tire slip would be corrected with a rear/inside wheel brake application.
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      04-05-2013, 12:03 PM   #26
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Originally Posted by CanAutM3 View Post
I am not sure front wheel lift is what is causing MDM intervention. Watching the video, most of the time it is the front/outside wheel that is being braked. This is consistent with a stability system wanting to correct/prevent and oversteer condition. IMO, a front tire slip would be corrected with a rear/inside wheel brake application.
I'm willing to bet a swift kick in the @ss that he's got his brake signals crossed, or the data software is mapping the wrong brakes, left and right.
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      04-05-2013, 12:24 PM   #27
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Originally Posted by The HACK View Post
I'm willing to bet a swift kick in the @ss that he's got his brake signals crossed, or the data software is mapping the wrong brakes, left and right.
So if the front brake signals are crossed, that would imply that MDM is braking the inside front wheel. Now why would a stability system brake the slower rotating wheel (the one that is lifting) ?

I believe that the answer is much simpler. IMO, MDM is simply anticipating a potential oversteer and is applying outside front brake to correct. As was mentioned by Bigjae, a square tire setup would accentuate this type of MDM intervention.
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      04-06-2013, 11:28 PM   #28
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Quote:
Originally Posted by CanAutM3 View Post
So if the front brake signals are crossed, that would imply that MDM is braking the inside front wheel. Now why would a stability system brake the slower rotating wheel (the one that is lifting) ?

I believe that the answer is much simpler. IMO, MDM is simply anticipating a potential oversteer and is applying outside front brake to correct. As was mentioned by Bigjae, a square tire setup would accentuate this type of MDM intervention.
Agree. NFW it's touching the inside front wheel in a turn. If it were understeering, it would brake the inside rear wheel.
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      04-06-2013, 11:30 PM   #29
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Quote:
Originally Posted by aus View Post
Next time you're in LA or OC, it can be done for $60, and that includes anything else you want coded; like the Accept screen delete, folding mirrors with the door handle or key fob or anything else you may want. It's a flat rate. I haven't checked out the Vegas forums to see if anyone does it there.

Of if you have the time and know computers: bmw coding(one word) dot com

.

And that Nascar 1/2 at AAA definitely gives the regular MDM fits... which makes the rear end wiggle . I haven't tried with Euro MDM yet.

.
Thanks. Not sure when I'll be in LA. Restraining order and all that...
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      04-07-2013, 10:22 PM   #30
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Quote:
Originally Posted by DallasBoosted View Post
People drive on the track in anything but DSC OFF?
Isn't that some ****?

The sad thing about all those new electronics is that it breeds a new generation of drivers that pretty much don't know any better. Hell some defend it. I wonder how people used to do before this stuff existed
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      04-08-2013, 12:31 AM   #31
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I had a ride at AAA with Judy (CCA instructor who works at Crevier) and she said she keeps MDM on and she drives with MDM on and I don't think she knows about the Euro MDM. Ti-Jean did mention it to her in the classroom session and she was not aware of it.
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Let me get this straight... You are swapping out parts designed by some of the top engineers in the world because some guys sponsored by a company told you it's "better??" But when you ask the same guy about tracking, "oh no, I have a kid now" or "I just detailed my car." or "i just got new tires."
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      04-08-2013, 03:03 AM   #32
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Quote:
Originally Posted by kaiv View Post
Quote:
Originally Posted by DallasBoosted View Post
People drive on the track in anything but DSC OFF?
Isn't that some ****?

The sad thing about all those new electronics is that it breeds a new generation of drivers that pretty much don't know any better. Hell some defend it. I wonder how people used to do before this stuff existed
About 6 months before I went DSC off, I had a pretty prolonged argument on this forum with someone who was very insistent that DSC must be off when tracking (even mentioned that it's a must if you want to get a racing license, despite majority of HPDE people not having the interest, time nor the talent to go all the way like that).

Then, the next time I saw him at Buttonwillow, he ran half the day on MDM! wtf?
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      04-08-2013, 06:21 AM   #33
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Quote:
Originally Posted by kaiv View Post
Isn't that some ****?

The sad thing about all those new electronics is that it breeds a new generation of drivers that pretty much don't know any better. Hell some defend it. I wonder how people used to do before this stuff existed
F1 cars have a form of MDM, so do Le Mans Cars, so do DTM cars.... there was a vid of DTM driver explaining MDM slip angles. It's not a bad thing to have on a track. Say Nordschleife, you better be rich to run without. Many pro's crash on the ring.

I wish we could program MDM more than euro mdm... I think US is 4% slip vs Euro is 7% slip. Wish we could do like 10-11%... I just need that little bit more....
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      04-09-2013, 01:49 AM   #34
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Quote:
Originally Posted by kotik View Post
F1 cars have a form of MDM, so do Le Mans Cars, so do DTM cars.... there was a vid of DTM driver explaining MDM slip angles. It's not a bad thing to have on a track. Say Nordschleife, you better be rich to run without. Many pro's crash on the ring.

I wish we could program MDM more than euro mdm... I think US is 4% slip vs Euro is 7% slip. Wish we could do like 10-11%... I just need that little bit more....
F1, Le Mans, DTM etc are top of the food chain race cars. Multimillion dollar engineering, big stakes, competing to win etc.

It's just silly to compare them to our peasant street cars we drive at DEs on Sundays. There is no DE championship or stakes here.

Learn to drive with your own steering, throttle and braking inputs. It's also more rewarding.
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      04-09-2013, 05:53 AM   #35
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Quote:
Originally Posted by kotik View Post
F1 cars have a form of MDM, so do Le Mans Cars, so do DTM cars.... there was a vid of DTM driver explaining MDM slip angles. It's not a bad thing to have on a track. Say Nordschleife, you better be rich to run without. Many pro's crash on the ring.

I wish we could program MDM more than euro mdm... I think US is 4% slip vs Euro is 7% slip. Wish we could do like 10-11%... I just need that little bit more....
Traction control and stability systems have been banned from F1 quite a few years ago. This was done to put more of the driving in the drivers hands .
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      04-11-2013, 12:17 AM   #36
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Just my 2 cents about MDM, I will use it on a new track or if I'm trying to get comfortable with a car or want to push the car more than normal in a very high speed turn to build confidence then turn it off. I.e willow springs turn 8 going from 124 to 129. To be honest it's a bit nerve wrecking and a little extra confidence is nice. Already spun an Evo at 130 there ;(
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      04-11-2013, 08:31 AM   #37
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I could definitely feel MDM grabbing the rear wheels coming out of corners on the gas. It was like a quick "bam bam bam bam bam" feeling. At first I thought my car was bouncing in the rear and I had rebound dampening issues.
Took a picture of the rear rotor yesterday while putting street pads back on. You can see the notches from where the brake pads were hitting the rotor intermittently. Must have been pretty hard, because I ran entire day after that with DSC OFF and notches are still visible.



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      04-12-2013, 02:32 PM   #38
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Quote:
Originally Posted by kotik View Post
It's not a bad thing to have on a track. Say Nordschleife, you better be rich to run without. Many pro's crash on the ring.
FWIW, the two times I was at the BMW Club Europa's 'ring school, I always drove with traction control off (2002 M3, 2003 330i ZHP). I drove the A1-ring in a driving rainstorm with the TC off in 2002. No big deal if you know what you are doing, though we had the benefit of Derrek Bell giving us pointers on driving in the wet so we may have had a *slight* advantage. Drive within your talent limits and TC is unnecessary.

I've seen a car crash b/c the traction control was on (it was very wet) but the skilled driver could not control the car with all the electronics trying to save him. It may have been better for him to just take his hands off the wheel for all the good the electronics did him.

The E9x is a bit of a problem b/c of the outstanding power of the car, the grip of modern tires being close to or exceeding the r-comps of old, and the very limited capabilities of the drivers, myself included. Couple these with the mass of the E9x platform, and you have a very high kinetic energy car with drivers thrashing it around like it is an E30M3 on forgiving tires. Big problems await.

In 1995 with the E36M3 we had these same discussions b/c we knew no-one at the track was as capable as the car was. People went off track with abandon back then too.
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      04-12-2013, 04:37 PM   #39
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Quote:
Originally Posted by admranger View Post
FWIW, the two times I was at the BMW Club Europa's 'ring school, I always drove with traction control off (2002 M3, 2003 330i ZHP). I drove the A1-ring in a driving rainstorm with the TC off in 2002. No big deal if you know what you are doing, though we had the benefit of Derrek Bell giving us pointers on driving in the wet so we may have had a *slight* advantage. Drive within your talent limits and TC is unnecessary.

I've seen a car crash b/c the traction control was on (it was very wet) but the skilled driver could not control the car with all the electronics trying to save him. It may have been better for him to just take his hands off the wheel for all the good the electronics did him.

The E9x is a bit of a problem b/c of the outstanding power of the car, the grip of modern tires being close to or exceeding the r-comps of old, and the very limited capabilities of the drivers, myself included. Couple these with the mass of the E9x platform, and you have a very high kinetic energy car with drivers thrashing it around like it is an E30M3 on forgiving tires. Big problems await.

In 1995 with the E36M3 we had these same discussions b/c we knew no-one at the track was as capable as the car was. People went off track with abandon back then too.
The E9X M3 (and the E46 for that matter) has another little hidden devil, it's hidden in the M-differential when driving in the wet. The M-differential is great to power out of corners or to do nice controlled drifts. However, when you hit a big enough puddle of water with only one rear wheel while under full acceleration, the differential will send all the power to the opposite wheel. This will instantaneously throw the cars sideways . Ask me how I know .

This one of the reasons I believe it is more prudent driving with DSC or MDM activated on a wet track.

Last edited by CanAutM3; 04-12-2013 at 05:02 PM..
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