As others have said, stock 260HP. Personal preference would be a rebuild from Barrett, Aerosports, or Ly-Con. Prop: Hartzel Blended 2 blade. 3 blades look sexy, but you will loose speed and the cowl is harder to get off.
Our -10: Stock IO-540-EXP (Airflow FI) 260 HP, Harzell prop. Real life TAS @ 8500 ft, 177 knts @ 14 GPH. We're not set up for LOP yet, so I can't comment on that.
40569, flying. 190 awesome hrs so far. Currently down for paint.