Ford is the only one left running it of the big 3 in a 3/4 or 1 ton pickup. GM went to Denso hp4 injection after all the cp4 failures. Even after Bosch switched to the symetrical cam cp4, Cummins talked FCA into dropping the CP4, and going back to a CP3 with talk of retrofitting 19-20 models from a CP4 back to the CP3 when the CP4 fails. There is talk as well of them going to Denso HP4 injection for 22 or 23 because of the CP4 failures. So far Ford is the only holdout of the big 3, but a CP4 is still the best option for a V8 to run sustained injection pressures in the sub 40,000 psi range.
The CP4 is 2 pistons that get actuated 2 times per CP4 revolution. The pump is timed when installed which allows it to pump fuel when the injector is open so that the CP4 pump output pulses match the injector firing. This allows for it to run the highest possible pressures since you cannot get a CP3 to get it's output pulses yo match up yo the injectors firing on a V8 since the CP3 is 3 cylinders that pump once per CP3 revolution. But the CP3 DOES match up to the 6 cylinder Cummins perfectly.
When the only way possible to meet emissions is to run enough fuel pressure to cut steel plate if you used the correct nozzle, they will do whatever is necessary to do it, and the CP4 is the best option from Bosch to run 36,000-39,000 psi of fuel pressure. Last I heard was to expect 48,000-52,000 psi of fuel system pressure in the near future.
