Here's my settings. They are from the very top of the RealFeelPlugin.ini;
[General]
RealFeelIsOn=True
ConsoleEnabled=False
ConsoleRepeatDelay=0.100000
SpeechEnabled=False
KeyRepeatDelay=0.100000
SteerForceInputMax=11500.000000
MinSpeed=0.000000
DefaultMaxForceAtSteeringRack=-2000.000000
DefaultSteeringDamper=11500.000000
DefaultFrontGripEffect=0.200000
DefaultSmoothingLevel=0
VehicleDelimiterSize=5
DefaultKf=11500.000000
DefaultKs=7.000000
DefaultA=1.000000
DefaultKr=3.000000
Logitech Profiler settings are as follows....
Use special force feedback settings (ticked)
Overall Effects Strength - 107%
Spring - 0%
Damper - 0%
Enable Centering Spring (ticked)
Centering spring strength - 0%
Use special steering wheel settings (ticked)
Report combined pedals (un-ticked)
Degrees of Rotation - 540
Use Special Game Settings (ticked)
Allow Game to adjust settings (un-ticked)
Hope this helps.
Anything else you need we'll see what we can do.