Hi French Frie,
the numbers look a bit odd to me. The formula to calculate Ps or Kilowatt is P[kW]= Md[Nm] x n[1/s]
To make it easy, we can say, PS = Newtonmeter x rounds per Minute
Ps and Newtonmeter after the tuning seems to be measured at around 6200 rpm for all cars in your table, that looks ok and the result is reasonable for each car. What does not fit into it, are the figure before.
Your result before tuning for example, gives a result of 423 Newtonmeter, which is 23 NM more as the specs. At 6200rpm that should deliver 373 PS, which is pretty much what you have today