Launch Control ( Gas Pedal ) - The Unofficial BMW M5 Messageboard (m5board.com)

///M Phobia · 27th August 2007, 08:20

I'm just curious as to how everyone does launch control. Do you guys have your foot all the way on kick down or right before kick down?

RussRamz · 27th August 2007, 09:20

All the way to the kick-down switch.

holmesmd · 27th August 2007, 16:52

What "kick down switch" are you referring to Russ? I don't use it often but when I do, I have the accelerator to the floor boards. I release the shift lever and away I go!!

RussRamz · 27th August 2007, 17:01

If you depress the throttle to the floor, you will feel a gentle click. That click you feel is the kick-down switch that enables launch control.

holmesmd · 27th August 2007, 17:21

Sweet! To be honest, not sure I ever noticed the switch but it makes sense. I am always too busy trying to focus my cheesy grin on the road ahead

///M Phobia · 27th August 2007, 20:54

When i did launch control with the kick down pressed all the way, my launch wasn't that great. But when i pressed it down right before kick down, the launch was much nicer, has anyone had that problem or is there something im doing wrong?

RussRamz · 27th August 2007, 22:48

Quote:

Originally Posted by ///M Phobia

When i did launch control with the kick down pressed all the way, my launch wasn't that great. But when i pressed it down right before kick down, the launch was much nicer, has anyone had that problem or is there something im doing wrong?

What do you mean by 'wasn't that great' and 'much nicer'?

///M Phobia · 28th August 2007, 00:09

Quote:

Originally Posted by RussRamz

What do you mean by 'wasn't that great' and 'much nicer'?

Im saying that when i did the launch control without pressing the kick down, by nicer i mean that it actually felt like a launch and the revs jumped a lot higher.

RussRamz · 28th August 2007, 08:45

Quote:

Originally Posted by ///M Phobia

Im saying that when i did the launch control without pressing the kick down, by nicer i mean that it actually felt like a launch and the revs jumped a lot higher.

That's the point of launch 'control'. When you start, the program will resist the tendency for your tires to break lose and spin, thereby maintaining as much traction as possible by automatically feathering the throttle for you in first gear. As things settle down and you hit red line with the car fully gripping the pavement, you have to shift to the next gear since the US launch control won't do it. This is the reason why many people using the US version are not doing it correctly and don't fully depress the kick-down switch allowing their cars to 'sit and spin'--going nowhere, but making a lot of rubber smoke. Gustav has some grand finale videos at the Sweden airfield event that demonstrates the effectiveness, but he might be saving it for the next DVD.

gasterus · 28th August 2007, 19:35

Hi Russ,

I thought the US-spec M6/5 has a tone down launch control...not sure if they are able to smoke as much tires as the euro-sec M cars :-)

RussRamz · 28th August 2007, 19:39

Quote:

Originally Posted by gasterus

Hi Russ,

I thought the US-spec M6/5 has a tone down launch control...not sure if they are able to smoke as much tires as the euro-sec M cars :-)

Yes, that's right. The LC in US Spec'd cars only begins at 1,400 RPM, where the Euro models start at 4,000 RPM. In both cars, the throttle and clutch are automatically modulated to reduce wheel spin, but in addition the the 1,400 RPM limit in the US Spec'd cars, ours won't auto-shift like they will in the Euro models. In both cases, wheel spin is limited. Those that don't fully press the kick-down switch and begin with the 1,400 RPM will end up turning their tires to smoke...