I'm no expert, but to me it looks like two power runs rather than a before and after comparison.
How many runs did you do? Could be that the wrong two were selected for the graph maybe? I don't know, don't wish to speculate really as Paul knows his onions but that to me, looks like two power run like what you'd do on a shootout day. The traces are near as makes no difference identical, although gains are hard to come by on these engines this does still seem a small gain to be honest...
Completely ignore the BHP numbers and just focus on the gain and trace.
How many runs did you do? Could be that the wrong two were selected for the graph maybe? I don't know, don't wish to speculate really as Paul knows his onions but that to me, looks like two power run like what you'd do on a shootout day. The traces are near as makes no difference identical, although gains are hard to come by on these engines this does still seem a small gain to be honest...
Completely ignore the BHP numbers and just focus on the gain and trace.