It's all down to how you map the car, such as using throttle multipliers as well as top line extrapolation. In an ideal wolrd we would'nt do this, but since not everything is ideal, there are ways around it that are very reliable.

I usually run anything up to around 6psi over the map sesnors range and find this causes no problems in terms of being able to map it. i.e. up to 23psi on a 2bar and 36psi on a 3bar.