How can you get 400hp out of a 2004 Dodge ram 1500 hemi?

To achieve 400 horsepower from a 2004 Dodge Ram 1500 with a Hemi engine, you can start by upgrading the intake and exhaust systems to improve airflow, such as installing a high-performance cold air intake and aftermarket exhaust headers. Additionally, reprogramming the engine's ECU with a performance tune can optimize fuel delivery and timing. Installing performance camshafts and upgrading the fuel injectors can also contribute to increased power output. Finally, consider adding forced induction, like a supercharger, for a significant boost in horsepower.