You would have to get straight pipes(no muffler or baffles). The computer can not do anything cause there is no electronics in the exhaust pipes.
Baffle:
A partition or separator within a liquid tank, used to inhibit the flow of fluids within the tank. During acceleration, turning, and braking, a large liquid-filled tank may produce unexpected forces on the vehicle due to the inertia of liquids.
There are mufflers that he can get which will open up the exhaust and make a much nicer sound while keeping it compliant but they're expensive.