Your problem is you have given a max power RPM far too high. You are going to have great difficulties getting any exhaust through at that rev's. You need to claim ignorance and say you have spoken to the engine builder and the max power is at 3,500rpm. This is what I and most other people quoted and means the test is done at about 2,000rpm. If they wont accept you gave them the incorrect rpm power ratio not sure what you are going to do.
