[TiltedBrim]

Good morning all, a friend and I had a discussion last night over which is the fastest way to launch a 550i. Myself, being the owner of a 2011 F10 550 and a frequent observer of these boards think that Sport + which disengages traction control is the quickest way to launch the car. He feels that that totally goes against the purpose of traction control and that the fastest launch would have to have traction control engaged.

Could someone please verify this w/o me having to go out with a stop watch to a lonely road... Which honestly would probably be more fun.

Car is rear wheel drive, no X Drive and has the M Sport package and no performance upgrades yet... Thanks

[SirNicholas]

I'd be interested to know as well. I've heard Sport+ and launching out of 2nd gear is the quickest.

[Jmo550]

hold dsc until you see its fully off.

put it in manual in 2nd gear

and the brake and gas pedal
rev it up to 2-2.5k rpm

and enjoy

[Russkey]

Do you guys think it's safe to break the power till 2,500 rpm on xdrive?

[SomeRandomer123]

Originally Posted by Russkey

Do you guys think it's safe to break the power till 2,500 rpm on xdrive?

That's a good point.

Hopefully the torque converter will just take the stick as it would on a RWD.

[TiltedBrim]

Thank you Kjeronimo for your reply but why 2nd gear?

[alextremo]

Originally Posted by tilted brim

Good morning all, a friend and I had a discussion last night over which is the fastest way to launch a 550i. Myself, being the owner of a 2011 F10 550 and a frequent observer of these boards think that Sport + which disengages traction control is the quickest way to launch the car. He feels that that totally goes against the purpose of traction control and that the fastest launch would have to have traction control engaged.

Could someone please verify this w/o me having to go out with a stop watch to a lonely road... Which honestly would probably be more fun.

Car is rear wheel drive, no X Drive and has the M Sport package and no performance upgrades yet... Thanks

It depends on how skilled you are at controlling the throttle with your right foot. DTC/DSC work by cutting fuel and pulling timing to the engine to reduce power going to the wheels when they start to spin. This takes some time to recover from when you regain traction and will slow you down. If you can manage the throttle input to where you're just reaching the point of losing traction without excessive wheel spin you will have a faster launch with it off. This is especially important for non-xdrive cars like ours!

Sounds like your friend may be thinking of launch control, not stability/traction control like we have on the 550. Similar concepts but different implementations.

[alextremo]

Originally Posted by tilted brim

Thank you Kjeronimo for your reply but why 2nd gear?

These cars have so much torque at low RPMs (and 1st is relatively short) that you can launch from second and not bog down the engine. This saves you a shift if you were timing your run, giving you a quicker time.

This really applies to automatics - I wouldn't risk my clutch trying this on a 6MT.

[JamRWS6]

Never tried in 2nd but I can't think this would be the same in a 535.

[qadhi79]

press and hold brake..move to 2.5k rpm..launch
as soon as you feel your tyres gripping the road..WOT

I must add that this brake launching puts serious strain on the transmission and will shorten the life of your torque converter so do not try this too much..I have read somewhere that this "launch control" activity is logged in M5 and may even void your warranty!

[Richard Cranium]

Originally Posted by qadhi79

I must add that this brake launching puts serious strain on the transmission and will shorten the life of your torque converter so do not try this too much..I have read somewhere that this "launch control" activity is logged in M5 and may even void your warranty!

The M5 doesn't have a torque converter so you're comparing apples to oranges when talking about hard launches.

But yes, spending to much time holding the car with the rev's up is not great for the torque converters in a non DCT transmission.

[qadhi79]

Originally Posted by Richard Cranium

The M5 doesn't have a torque converter so you're comparing apples to oranges when talking about hard launches.

But yes, spending to much time holding the car with the rev's up is not great for the torque converters in a non DCT transmission.

True, M5 does not have a torque converter and I was only making a point that even cars like M5 do not like such beatings again and again..better safe than sorry