ACC: Bumpstop telemetry in the setup screen

[VELOCIPEDE]

Fonte ACC forum

Yes you're right, I wanted to explain it, but was running around with the release, sorry. So:

Yellow line:
Suspension movement. Obviously the car is stopped at the box so no movement but this is where your suspension "sits". While driving, imagine the suspension line moving up and down. Up when the suspension goes into compression, down when it extends.

Red line: 
Bumpstop (up) point. By changing the "bumpstop range" value (which we should better name it bumpstop gap), you modify the space between the suspension "free" travel (only springs) and when it touches or presses the bumpstop. The closer the red line goes to the yellow line, the sooner the suspension will start compressing the bumpstop and this raising stiffness and controlling the suspension compression movement.

Green line:
Just the end of suspension travel in extension. Not in scale, safely ignore.

Small reminder; As you know by now, cars that have important aerodynamic features as splitters and diffuser, are quite pitch sensitive. That means that when you brake the car pitches forward, making the front splitter going closer to the ground and the rear diffuser going further up from the ground. The effect of that is that the aero balance moves heavily towards the front of the car. If this pitch movement is not constrained, the car can become very unstable especially under trailbraking turn in.

How to setup the car?
Rule of thumb (but as always your mileage may vary, it's all a compromise).
The more stability you need under turn in, the more you need the front suspension to touch the bumpstop when pitching forward. So to make the car more stable, you need to lower the "bumpstop range" value so that the redline goes closer to the yellow or even touches it. Obviously if you need more turn in, then you go the other way around. You can also modify the stiffness of the bumpstop by increasing or decreasing the "bumpstop rate". Later on you it will be also possible to change the linearity. (note: rear wing can stabilize this effect too making it more mild and permitting a suspension with more gap until the bumpstop (or softer bumpstops).

Generally you want less bumpstop work at the rear, so that the rear end absorbs kerbs and bumps and gives traction. Still, if the circuit permits it and driving style can handle it, you can do similar setup to the rear. Making the suspension touching the rear bumpstop sooner, you raise the stiffness and also limit the squat of the rear end, preventing the aero balance of shifting too much to the rear and limiting power on understeer.