GalaxySurfer
Life, The Universe and Everything.
1. Ludicrous+ Mode
2. Battery heated
3. Press and hold brake and press accellerator to the floor and release and you should see Launch Mode on your instrument panel
4. Floor accelerator and release brake to launch
Battery needs to be heated, that is what most people miss. Other than that it is the simplest launch mode I have used.
Its also important to note:
The car NEEDS to be in low or very low air suspension as well, or you will just get the both pedals pressed message.
Edit: the battery also doesnt need to be fully heated, just turned on via ludicrious+