A medium downforce circuit in the dry, such as COTA, becomes a fairly high downforce circuit in the wet, as more aerodynamic grip is required to deal with the tricky conditions.
Specifically, I would run 4-9 wings around here. This will have you understeering a little through the first sector, but the stability the setup provides you with more than makes up for that.
An on-throttle differential setting of 50% is a must-have at any wet race. It gives you a far easier time during traction than you would usually have.
For the off-throttle setting, I’ve gone for 70%. This is low enough to help the car with rotation through the corners but not so low that the car becomes unstable in the turns themselves.
Opting not to run much camber has a similar effect to running a fairly high off-throttle differential setting insofar as it brings stability mid-corner at the cost of performance.
Once again, I believe this is a trade-off well worth making. As such, I recommend using -2.50 and -1.00 camber settings.
For the toe of the wheels, the minimum settings of 0.05 and 0.20 work really nicely during sustained cornering situations at little cost.
Of course, it’s beneficial to run a soft suspension setup in wet conditions, to ensure that the car remains predictable.
However, you can’t go all the way to 1 for your front and rear suspension stiffness as you will find your car incredibly sluggish through the first sector. 2-3 is about as low as I would recommend going here.
For your anti-roll bars, I suggest 9-9. This helps to keep the car from washing wide halfway around a corner, which is a major issue in the wet if left unchecked.
A high ride height is crucial in the wet. 9-11 gives you plenty of clearance over the slippery track below.
I always like to run 100% brake pressure along with 50% brake bias in F1 2020. I find that it gives me the best stopping power without causing me to lock up my front tyres too often.
However, everybody is different. If you prefer a softer brake pedal, then feel free to run a lower brake pressure than I have suggested. It’s all about personal preference for the brakes.
Tyre pressures, however, are less open for negotiation. Lower tyre pressures help you to maintain a stable, predictable car in conditions which are anything but.
Therefore, going with 22.2psi on the fronts along with 19.5psi for the rears is the way to go in Austin.
With this setup, you should find that your car can handle any challenge a rain-soaked COTA can throw at it with ease.