In the settings folder find your rudderpeddles.jsm file. Open it with notepad. Find the following line and crop 5000-10000 off each end of the calibration line.
Uncropped line:
Rudder
0,32767,65535,0.050000,0.100000,0.250000
These numbers represent your full left, centered and full right deflection when the calibration app tells you to perform those tasks. By shortening the ends you speed up how fast your rudder deflects relative to your hardware input.
0,32767,65535
My cropped siatek rudder peddle line:
Rudder
17000,32767,49767,0.082000,0.110000,0.250000
What this does is shortens the full deflection needed from your controller input to achieve the deflection you watch while you push your peddles. You will suddenly need much less input to snap out a full deflection because the numbers in the file now tell the game your full deflection is about 3\4 of what it used to be. This translates into a higher rate of deflection in real time. In the end you will have to apply scaling, dead band, and delay to slow it down or you will over control without trying. It will be necessary to have a very slowed down center transition so you have fine control of the first 1\4 deflection off center on each side.