The baseline for the P31 C63 on the dyno graph below from a Dyno Dynamics is 390 and 394 wheel horsepower reflected in the blue and pink lines respectively. Tuned, this rises to 427 and 421 wheel reflected in the green and red lines.
Compare this to a standard C63 AMG which puts down 363.6 wheel horsepower stock, the grey line. Tuned, this rises to 421.3 which is the orange line.
So, the P31 is obviously much stronger in stock form. When tuned, both cars end up around the same spot. This is really the first dyno graph posted on BenzBoost showing solid gains on top of a P31 optioned C63 car.
Very, very nice results by OE Tuning. The graph is below and BenzBoost is attempting to source a higher resolution graph.