I have read in the A45 and CLA45 AMG forums that besides the race start, there is also another "soft launch" function by setting Sport handling mode and S in gearbox, left foot full on brake and right full on throttle. I tried this but in my GLA with 1200km but the rpm did only go up to 1100 and not 3000 as it was supposed to. Has anyone tried this and confirmed that it works in our cars?

 

No did not work for me MY14 ... shame

 

There is no soft launch for the GLA. However, if you floor it normally from a stop, the revs build to 3k and then you're gone.

 

Looks like AMG pulled the soft launch option as its not possible on 2015 CLA45's either. I was able to do it with my 2014.