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Discussion Starter · #1 ·
Hi guys, hoping someone can confirm my experiences with my M5. I have an Australian delivered car, which from factory has the European SMG tune, which is supposed to have a pretty good launch program, which automatically upshifts and maintains traction by varying the clutch engagement (the throttle must be kept fully depressed at all times)

However, with my FAMS tune all I get is a smoke show, and no automatic upshifts.

Anyone have similar experiences?
 

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Its been a while since I used LC but from memory you should be in S not M for the trans (and dsc off etc) and you must keep your foot buried past the kickdown switch. Mines does shift for me.

As far as the smoke show goes it’s performance is pretty variable and a lot depends on the surface and what tyres you have.

I’ve had some really good launches and some long rolling burnouts.

At the end of the day it’s trying to launch a fairly heavy car, with rwd, with 500hp from 4500rpm, that’s a tough ask. It’s a fine line between maximum acceleration with perhaps a little tyre slip and roasting the tyres. It really depends a lot on your tyres too. Hard, old, worn tyres have a low grip threshold and once spinning the wheel speed goes up faster than the car can react. Really good tyres help the car modulate the clutch (edit: ok, maybe it’s just modulating the throttle to try and maintain traction, or maybe it’s doing nothing) to keep it right at the traction limit.

As far as the fams tune cancelling euro LC. I’m not sure. I don’t have a tune.

Edit: I have noticed if I do 2 launches on the same surface (after a short drive to let everything cool) the second launch is much better. I’m not sure if it learns or if it’s just from heat in the tyres but it’s noticeably better.
 

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Discussion Starter · #4 ·
Good point about the tyres and the reaction speed of the car. Could indeed be the cause.

I can confirm my car does activate LC as it holds ~4K rpms. As mentioned in the first post I was extra careful to press and hold the lockdown switch.
 

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this is totally nor true! SMG has never modulated the clutch pressure, it just dumps it . I am running FAMS for 3 years together with EURO SMG from fact and it works just like was meant to work
US smg dumps the clutch at 1.5k and doesn't shift. Euro is supposed to modulate, launch at 4k with adjustment through the cruise control lever and auto shifts.
 

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US smg dumps the clutch at 1.5k and doesn't shift. Euro is supposed to modulate, launch at 4k with adjustment through the cruise control lever and auto shifts.
90% you are right, but the most important 10% unfortunately not... it does not modulate at all, just dumps it and then hits the rev limiter and bounces there 2-3 times until finally goes in 2nd gear thus loosing tremendous time. If you heave really good grip like you would have maybe with semi slick or drag radials on concrete I believe it would shift faster in 2nd, but still it would not modulate. Also I find it better to reduce rpms at 3500 , otherwise at 4500 it is even worse , it is not launching, just spinning like crazy
 

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Now you all are tempting me to do my first LC and next waiting for the flatbed as I can't guarantee the health of my unknown history SMG, so please say 'DON'T DO IT". I do have EURO M5 and latest SMG 2206 tune though.:D
 

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Discussion Starter · #9 ·
90% you are right, but the most important 10% unfortunately not... it does not modulate at all, just dumps it and then hits the rev limiter and bounces there 2-3 times until finally goes in 2nd gear thus loosing tremendous time. If you heave really good grip like you would have maybe with semi slick or drag radials on concrete I believe it would shift faster in 2nd, but still it would not modulate. Also I find it better to reduce rpms at 3500 , otherwise at 4500 it is even worse , it is not launching, just spinning like crazy
What you say about hitting the rev limiter twice then shifting is also an interesting point. I have not held it to the point of bouncing off the rev limiter, but instead aborted and took over control myself.
I wonder if perhaps as suggested earlier, that it is an issue of response time by the LC program, and therefore highly dependent on the mechanical grip. This bouncing off the limiter to me is further evidence of a latency issue.
What tyres are you using?
 

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When I had the Euro Tune in I would call it "launch out of control" lots of tire smoke. I did just read recently that you have to have the pedal on the button or it will not shift. To be honest I was never able to hold the pedal down that long. I just shifted on my own and beware in S6 on the button after the car shifts the tire smoke will continue. I think I recall a third set of tracks as well but by then the car is moving so fast that it's easier to control. Looks really cool, tire marks, small gap, more tire marks, small gap, more tire marks.
 

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The first time I tried euro smg I had snow tires on. It ended up with baaaad clutch smell as it was modulating the clutch to keep tires from spinning. But no burnout. When I switched to regular tires it literally put a smile on my face. No burnout either. When I flashed a somewhat local guy's car we went for a test and same story - autoshift and no burnout. Before all this when I tried US launch (at 1.5k) now that was a clutch dump with smoking tires but car wasn't going anywhere. Weird that we've all had different experiences.

I did just read recently that you have to have the pedal on the button or it will not shift.
This ^^^
 

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The only description in the drivetrain PDF is useless:
Launch control has been carried over from the E46 M3.

Was trying to find a similar document for the e46 but no luck. Anyone knows of a training document describing launch control on the e46?
 

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I've had both on my originally Euro delivered car. I've now got another tune as I couldn't resolve pinging with the FAMS tune installed.

That said, you do not keep your foot buried. That's just for initiation. Once rolling you need to manage wheel spin by modulating the throttle. And definitely, absolutely, positively not in auto mode.
 

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My experience of the euro LC is that is pretty wild and there can be plenty of wheel spin, but the car is definitely doing something to attempt to manage the wheel spin. I can’t say whether it’s slipping the clutch or modulating the throttle (my feeling is clutch). And it certainly upshifts without banging into the limiter for me.

On the other hand if it have the car in dsc off, M, S6 and get the car just barely rolling and then really stab the accelerator hard and pin it, I get a massive clutch dump, massive burnout, I shift to 2nd, still going and if I keep the throttle pinned I can maintain it into 3rd. That’s without using any brake. Part way through 3rd road speed is catching up to wheel speed traction comes back.

It’s kind of two movements. A quick maybe 20% throttle which gets the car rolling, quickly off the gas (clutch releases) and as you feel the clutch release you kick the throttle like you’re starting a motorbike with high compression. You have to do the whole thing fairly quickly and at low road speed. Otherwise it won’t open the clutch. But at low speed (low rpm) it has to open the clutch to stop the car either stalling or bucking, the second stab kind of surprises the car and it goes ‘oh ****, he wants to go, dump the clutch’ but by that time there’s already enough rpm on board to get the tyres roasting.

Of course I’d never suggest anyone try this. 😊
 

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I've had both on my originally Euro delivered car. I've now got another tune as I couldn't resolve pinging with the FAMS tune installed.

That said, you do not keep your foot buried. That's just for initiation. Once rolling you need to manage wheel spin by modulating the throttle. And definitely, absolutely, positively not in auto mode.
Huh... What's the point of lc then.
 

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Once I euro flashed there is some level of modulation, and even in manual mode first two shifts are cared for automatically and at the perfect point, 3-4 is where you pick it up and go. During the summer it’s a hell of a launch, and as flaco mentioned I think I probably giggled like a school girl the first time I did it properly. I did it a couple weeks ago on hard tires and the car allowed quite a bit more wheel spin-but still clearly not a clutch dump’s worth. If these cars truly just dumped and held WOT you’d go nowhere.
It only activates in manual mode, S6, DSC off, P500. Push the lever forward and hold it, foot off the brake, pin it all the way to the floor quickly and if the needle shoots up then wags it’s tail around 4 let Houston know we’re clear for takeoff.
 

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I always leave it pinned
Once launched its tempting to remove you foot off the throttle slightly and then it wont auto shift
Exactly, you have to fight the urge to lift at all. It’s natural to want to but if you keep it pinned and give it a chance it sorts itself out pretty quickly and if you do lift it disengages LC and then of course won’t shift for you etc.
 
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