Power Disc Brakes not working on hard stop?

On my ssbc setup, the pedal feels like it is hitting a mechanical stop. It doesn‘t seem to have that little bit of sponginess you get when pushing on the pedal harder on normal brakes.
Yes, That is the exact feeling I get with both systems (cars). I've traded emails with both Dr Diff and SSBC and neither have any suggestions for me. Are you also running 14 inch wheels with the small bolt pattern?