Forum: CP3 in Ram verses CP4 in Ford and GM

Discussion about Bosch HPFP CP4 applications on Ford and GM diesels, including details on the construction of the pump and why it's susceptible to failing:

It is in the laws of physics...

First, they used the fuel, diesel, as the CP4's internal's lube

Then the pure dumb @ss piston pump design. Piston to connecting rod
and that the rod is NOT connected to the cam. It floats on the cam
follower.

Think of any ICE's piston, wrist pin, connecting rod, rod caps holding
it to the crank shaft...think tossing the rod caps and just have the
rob bottom ride on top of the crank without those caps...it would
hammer itself to death quickly

The DLC (diamond like coating) on the cam or was it on the cam follower...
Regardless...another pure dumb @ss thing. Diamond is one of the best
'non-stick' materials known to mankind. Think lube film strength to
'film' (AKA wet) the surface of the worlds best non-stick surface. Diesel
is NOT designed as a lube...

All this and more doesn't happen in an instant, but over time. Spewing
debris into the fuel system..including DLC particles...one of the
hardest materials known to mankind

At 2,000 BAR (+29,000 PSI) the 'filter' would have to have the particulate
size filtration (capture and 'HOLD'). As the 'hold' builds up debris
the +29,000 PSI will try to rupture (explode) the filter canister
and tear apart the filtration material to then become debris for the
injectors...

Compare that +29,000 PSI for the fuel to the average gasser's combustion
PSI of around 1,000 to race ICE's at about 1,500 PSI...I don't remember
what diesel combustion PSI's are, but will look that up later

Not an easy fix for a dumb @ss design... NewsW was a very, very
smart guy and loved this comment: "Bosch engineers should be herded
onto cattle cars and shipped to Siberia" for their dumb @ss design...