After setting the ABS bias to the RS4 code I went out to log stopping distance a few times in order to compare with the previously recorded S4 bias distances. With the larger StopTech 332 brake setup on the front of the car the idea with making the ABS bias to that of the RS4 is on account of the RS4 using larger brakes than the stock S4.
After swapping out stock S4 brake components for the larger StopTech setup, you “should” update the ABS bias to match the new setup more closely, how true is that idea?
Here’s the results:
From these results it does not look like adjusting the ABS bias makes all that much difference to the stopping distance.
During three of the five S4 setting pulls the results were the same as what was achieved with the RS4 setting, or at least close enough that I consider the differences to be within a procedural margin of error.
It does not look like there is a significant benefit to changing the ABS bias from S4 to RS4 when upgrading the front brake setup. On the other hand, there’s no sign that doing so has any adverse affect.