I'll start by going straight in; when the December update drops, your driveline tuning page will look like this: With two new new additions: Engine Braking Reduction: This is something we always had to tinker with behind the scenes. The real power of this became apparent when we started to look at dialling out some tricky behaviours from some of our cars. Namely the off-throttle any-speed unrecoverable spins, also known as instabins. Some of us rarely had any trouble with such behaviour whereas others were very vocal. It turned out those who had little issue with it were naturally keeping a little bit of throttle applied at corner entry to keep the car stable. Those who regularly spun were completely off the accelerator pedal on entry. This lead us to realise that some drivers would benefit from a little bit of throttle being applied in order to reduce the engine braking and keep the car stable, even when they were not pressing their actual pedal. We also realised that would not suit everybody as agility is sacrificed. Thus the answer was to make it adjustable and that's when this slider was conceived. More clicks/higher values here will decrease the engine braking and make the car more stable when not pressing the accelerator pedal. It's worth mentioning that the name engine braking reduction was decided on as the normal English idle adjustment doesn't translate well to other languages, as it intrinsically linked to when the engine is at tickover revs and thus easily confused.