[hoyas490]

Originally Posted by choppedliver

My car has 1600miles on it and for the life of me could not get launch control on it tonight, for the first time. DSC Off, sports +, gear lever in manual/sports, mash the brake and then the throttle to floor. Revs climb to 3k and no launch control appears. I tried multiple times and even DTC off with no luck. Ieven did a dragy run on brake boost fine, just not able to engage launch control. I wonder if 2k miles is the trigger though the other thread says combined wisdom indicates that there is no run in period before it activates.

Very odd.

I'll be curious to try more this week / next couple of weeks.

I'm at 2,200 miles and my dragy runs were done between 1,300-1,600 miles. And they sucked.

Plus will be doing a big road trip down to South Florida next weekend, so will be getting a lot more mileage on the car. Maybe the extra miles and warmer temps for road/tires will help? But I'm cautiously not optimistic, and think there's something bigger going on that isn't atmospheric or mileage based.

[G35c6MT]

For launch control to activate, only TC should be off, not DSC.

Sport Plus, TC off, M/S gear position, level surface and wheels pointed directly ahead, full on brake+gas = LC flag in dash.

Not sure if auto hold is a factor but I’ve made sure to have if turned off first.

[choppedliver]

Originally Posted by G35c6MT

For launch control to activate, only TC should be off, not DSC.

Sport Plus, TC off, M/S gear position, level surface and wheels pointed directly ahead, full on brake+gas = LC flag in dash.

Not sure if auto hold is a factor but I’ve made sure to have if turned off first.

Thank you.

I did most attempts with DSC off and not DTC, will try again. I think I've not kept the accelerator down long. And it’s possible the wheels were slightly turned.

The brake boost run was good though 3.74 0-100. Compared to my 4.22 all the gains were from 50kmh and up. With LC perhaps 0-50 will be faster and a 3.6 is possible.

[remo999]

Originally Posted by choppedliver

........
The brake boost run was good though 3.74 0-100. Compared to my 4.22 all the gains were from 50kmh and up. With LC perhaps 0-50 will be faster and a 3.6 is possible.

That's good enough to destroy Dodge Challenger Scat Pack

[Cabbage]

Originally Posted by choppedliver

Thank you. The manual is confusing in that it says press the traction button (not hold), but then I’m sure the image shows DSC off.

I did most attempts with DSC off, will try again. And it’s possible the wheels were slightly turned.

The brake boost run was good though 3.74 0-100. Compared to my 4.22 all the gains were from 50kmh and up. With LC perhaps 0-50 will be faster and a 3.6 is possible.

Did you do that 3.7 time with the LCI M550i?

[choppedliver]

Originally Posted by Cabbage

Did you do that 3.7 time with the LCI M550i?

No, it's a non-DHP 2020. June 2020.

I've been following the thread and curious if the issue affected 2020s or not. My car was a low km demo that I picked up 6 weeks ago.

It appears the launch bug is not an issue.

I'm hoping to do an LC in the great weather we are having.

[PaLaKaT]

Originally Posted by choppedliver

No, it's a non-DHP 2020. June 2020.

I've been following the thread and curious if the issue affected 2020s or not. My car was a low km demo that I picked up 6 weeks ago.

It appears the launch bug is not an issue.

I'm hoping to do an LC in the great weather we are having.

Thats the issue, Looks like it only affects LCI M550s (Americans only?)
My friends 2020 M550 Pre-Lci puts down sub 3.9 all day long.

[choppedliver]

Originally Posted by DB_BMW

Thats the issue, Looks like it only affects LCI M550s (Americans only?)
My friends 2020 M550 Pre-Lci puts down sub 3.9 all day long.

Agreed. Finally got LC to engage on a dodgy surface and cut a 3.7 flat.

Found a better surface but it had warmed up too much and slower 3.88/3.9 with/without LC. There seemed to be a small pause before it goes which sounds like its exacerbated on the 2021s.

The 3.74 brake boost launch felt harder than the 3.7 LC launch, but the fronts did spin so perhaps LC does something clever.

With/without LC revs sit at about 2800. Is there a way to increase that? I tried with paddles and it changes gears so perhaps thats not a thing on 2020s?

I'd love

[BBDDVV]

Originally Posted by choppedliver

...
With/without LC revs sit at about 2800. Is there a way to increase that? I tried with paddles and it changes gears so perhaps thats not a thing on 2020s?

I'd love

In the past you could in/decrease the revs with the rocker button you use to increase/decrease the cruise control speed. Not sure if this is still the case though, but you could give it a try ;-)

[choppedliver]

Originally Posted by BBDDVV

In the past you could in/decrease the revs with the rocker button you use to increase/decrease the cruise control speed. Not sure if this is still the case though, but you could give it a try ;-)

Ahh, will try that. Thanks.

[PaLaKaT]

Good News.

Russians were able to unlock the ECU/DME on the new M8 and M5. I have already reached out to the guys to see if they can do anything for the M550.

Bad News (for me)

My damn iDrive is crashing again, not as often but at least 1-2 a day. I called the BMW NA and complained about that and the launch issue. They "noted" and they said "we cant do anything else". WTF?...

[choppedliver]

Originally Posted by DB_BMW

Good News.

Russians were able to unlock the ECU/DME on the new M8 and M5. I have already reached out to the guys to see if they can do anything for the M550.

Bad News (for me)

My damn iDrive is crashing again, not as often but at least 1-2 a day. I called the BMW NA and complained about that and the launch issue. They "noted" and that said we cant do anything else. WTF?...

That’s a bit shit. I’m surprised given press cars are having issues that they aren’t aware of the issue as that has to affect sales.

Have you just tried brake boosting. Leave traction control on and it won’t go into launch mode?

[igelkotten82]

New review of guys at Autotopnl and they are mentioning the problems with launch control.
But the big news in the video is that the car doesn´t reach its top speed of 250 km/h. Hard to try that out yourself without breaking a lot of rules as long as you don´t live in Germany..

[crypto]

Originally Posted by igelkotten82

New review of guys at Autotopnl and they are mentioning the problems with launch control.
But the big news in the video is that the car doesn´t reach its top speed of 250 km/h. Hard to try that out yourself without breaking a lot of rules as long as you don´t live in Germany..

I watched with audio off because I'm in a public place but not sure what you mean about the car not hitting 250 km/h? At 6m15s or so into the video the car his 255 km/h.

[Cabbage]

Originally Posted by crypto

I watched with audio off because I'm in a public place but not sure what you mean about the car not hitting 250 km/h? At 6m15s or so into the video the car his 255 km/h.

The old one would hit the limiter no problem. (260). The new one is struggling.

[PaLaKaT]

Originally Posted by Cabbage

The old one would hit the limiter no problem. (260). The new one is struggling.

To me it looks like its a soft limit issue not hardware. I noticed the car starts cutting power right before the actual soft limit.

Now i heard back from the tuner from Russia, they refused to do tunes over Internet. But the tune is possible! I guess its only matter of time till others find out how they accomplished unlocking the DME/ECU

[G35c6MT]

Originally Posted by DB_BMW

To me it looks like its a soft limit issue not hardware. I noticed the car starts cutting power right before the actual soft limit.

Now i heard back from the tuner from Russia, they refused to do tunes over Internet. But the tune is possible! I guess its only matter of time till others find out how they accomplished unlocking the DME/ECU

Can you ask them if it’s cutting power at launch?

[igelkotten82]

Originally Posted by crypto

I watched with audio off because I'm in a public place but not sure what you mean about the car not hitting 250 km/h? At 6m15s or so into the video the car his 255 km/h.

It says in the video that the car only makes 246 km/h on the gps (when showing 255). Official number should be 250 km/h like most Bmws.

[PaLaKaT]

My vehicle is back at the dealership... After replacing the head unit, iDrive stopped crashing for a day or two. Then crashed once a day but last couple of days it got worse. Today was the final nail in the coffin.. While i was reversing the vehicle in to a parking spot screen went black. I just took the car to the dealership and left it there, didn't get a loaner this time i decided ill just drive my 7 series until they fix it or something gets done. I called BMW NA and asked if they can just swap the vehicle for me because this is frustrating, brand new vehicle going to dealership for the 4th or 5th time for the same issue... I got a hold of a case manager from BMW NA and he should get back to me by next week... I really hope they fix it or replace the vehicle. If they do buyback i might consider new M5 instead of M550... The thing is though i really enjoy the softer drive on the M550.

[Boosted_8]

UK LCI M550i here. Need to put 100 more miles on then I plan to dragy test the 0-60. On a roll it feels a fair bit faster that my last car (tuned B9 Audi S4) that put down 3.6 seconds consistently. This UK spec car is on 20" Goodyear Eagle f1 runflats.

[PaLaKaT]

Originally Posted by Boosted_8

UK LCI M550i here. Need to put 100 more miles on then I plan to dragy test the 0-60. On a roll it feels a fair bit faster that my last car (tuned B9 Audi S4) that put down 3.6 seconds consistently. This UK spec car is on 20" Goodyear Eagle f1 runflats.

Originally Posted by Boosted_8

UK LCI M550i here. Need to put 100 more miles on then I plan to dragy test the 0-60. On a roll it feels a fair bit faster that my last car (tuned B9 Audi S4) that put down 3.6 seconds consistently. This UK spec car is on 20" Goodyear Eagle f1 runflats.

Cant wait to see the results you get!

[Boosted_8]

Only had time for two goes. First was a 4.1, second was a 3.9. Both using brake boosting only. I will have a go with Launch control this weekend via another road I've made my best runs on previously. I think there's another few 10's in her with a small combination of optimisations. This car is however 100% certainly boost / throttle by gear in the ECU. 1st and 2nd are quite soft, then once you hit 3rd you get the full show!