sigh…
Turning brake pressure up (slider moves right) above 100% does not help you brake/slow quicker. Your brakes are capable of transmitting stopping power to the ground ONLY if your tires have traction. Turning the brakes up, makes your brakes lock sooner. Turning your brake pressure down (slider moves left) increases your (brake) trigger travel. Doing this allows you a wider range of movement, allowing you to more easliy ride the ragged edge of brake lock up.
So, moving the brake pressure slider to the right, makes your brakes feel more like a light switch. Instant off. Instant on. Moving the brake pressure silder to the left makes your brakes feel much more like a light dimmer switch. More analog, you can control the point of lock up much easier.
My brake pessure varies according to each car, or class of car. My number plated racing cars, all have much higher downforce, much bigger brakes, and much better tire traction/grip. With these cars, i run my brake pressure up around 80%. On my lightweight, no downforce lower calssed cars, I tend to run about 73-74%. As for balance, that is very personal. I tend to trail brake. I trail my brakes on, after turn in. For this reason, I tend to run my balance toward the rear. Usually about 48-47%. With 911’s (rearward weight bias) I run 46-45%. On certain cars with extreme amounts of rear downforce (1970 Dodge Daytona), and little front downforce, I tend to also run the brake balance toward the rear a bit more (46-45%).
Brake balance toward the rear, keeps the fronts from locking up too early, but it can casue the rears to lock up a bit earlier. This gives the car a really uncomfortable, loose feeling heading into corners. I can deal with that, just fine, though, some popel, not so much. If your car is locking up the rears during braking, throw brake balance to the front a click or two until it stops. Also might be a good idea to move Differntial DECELL to the right a bit, too (about 50% of accell is good rule of thumb).
If you are locking the front brakes, then throw the balance toward the back. Decrease brake pressure if you are locking all four wheels. Note, you do want to be able to lock the wheels, you just don’t want it to happen, until your brake pedal (or brake trigger) is almost at full travel. Increase brake pressure, if you cannot lock the wheels; increase it until you can just lock the wheels.
Also, in high downforce cars the effect is really dramaitic. As you slow down, downforce decreases. this also removes tire traction. This is why brakes lock up at slower speeds on high downforce cars. Proper braking technique (in Forza, and IRL) is to slowly let up on the brakes as the cars slows, and loses downforce. This is true, even on NO downforce cars, but on high DF cars the effect is really dramatic.