There's even more Cummins 12-valve owners can do to add power besides fiddling with the P-Pump. With a different intake and exhaust, bigger turbos, a better lift pump, bigger injectors ...

Scott’s fun truck is the 1,200-plus horsepower “Ol Smokey” Cummins-powered ’49 Ford ... The final modification is a 165-gph 4G lift pump from PureFlow AirDog that replaces the stock ...

A Cummins engine's internal airflow—and methods ... the Hamilton head is roughly equal as far as flow until 0.200 valve lift, which is where the runaway starts. While the factory head shows ...

But among Cummins' 1990s offerings, the 12V designation is pretty important, as it refers to the sort of 12-valve engines ...