The VP44 24v didn't have any more emissions controls than the 12v in the traditional sense. No cat, no DPF, no EGR. It just ran cleaner because of tighter contr

The VP44 24v didn't have any more emissions controls than the 12v in the traditional sense. No cat, no DPF, no EGR. It just ran cleaner because of tighter control on injection timing and volume due to the switch from a purely mechanical pump/injectors to electromechanical pump in the VP44, then to fully electronically controlled injectors in the common rail after 2002. This change to electronic control is what made dial-your-horsepower and emissions skirting like this so trivial.