My car runs perfectly, no issues anywhere it was reading 298bhp on the first dyno run with no fault codes or errors. Then the new aggressive map was put on it. I should of got around 360bhp at least out of the map. But when dynoing with the new map it started of well. A good 20-30bhp than standard and torque was exceptional higher. However when hitting the 3500 rev the pressure dropped, this was shown on his diagnostic kit that was monitoring the engine. When it hit 200Psi the pressure dropped and the bhp levelled off. However there were no codes and no faults shown. How can I find out what the issue is? was it a mapping fault or was there a technical issue with a or some parts in my engine?