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This is probably not what you want to hear but....
No not really. It would also be illegal. The EPA regulates the emissions from all motors and no dealer or mechanic is allowed to change anything on the engine that would affect emissions. Anything effecting the horsepower also effects the emissions.
The engine parameters are all controlled by the ECU. You would have to change the ecu at the minimum, which is expensive.
So in effect none of the newer modern engines can be modified for more HP. At least not economically or legally.
Hopefully this answers your question. If you have further questions on this, let me know.