How do you turn up horsepower in a 12 valve cummins?

To increase horsepower in a 12-valve Cummins, you can start by upgrading the fuel delivery system with a higher-flow fuel pump and larger injectors. Additionally, modifying the turbocharger for better airflow and installing an aftermarket intercooler can enhance performance. Tuning the engine with a performance chip or ECU reprogramming will optimize fuel maps and boost levels, further increasing power. Always ensure that supporting modifications, like exhaust upgrades, are also considered to prevent excessive back pressure.