Gary,

The CP3 is just a plain old fashioned dual stage rotary pump. The first stage charges up to 900 PSI (I believe this is correct) while the second stage can pressure up to 30,000 PSI safely (in our applications, stock is 23,200).

Reliability on these CP pumps is beginning to be legendary in the trucking industry, which have been using common rail for years now.

As far as any similarity between the VP44 and CP3, they are both rotary pumps. Other than that, the CP3 doesn't share any real design or components with the VP44. Its just a dumb pump that merrily pumps fuel,much like the old 12 valve fuel transfer pumps. There are a couple ECM controlled pressure switches inside to regulate pressure, and thats about it.

Rod

 

Gary if you have the time and access, how about taking a trip to a Cummins shop and asking a few of the techs there for their take on that pump for reliability and function. I know Rod probably had the basic description down, maybe you can get some more technical specifics? Next time I am near a Cummins shop and/or Bosch, I will go and ask as well.
You never know, we might get different views...and then we can have a debate on here.

 

if the chevy pump is the same as the one on our Cummins then maybe you could go over to a Chevy site and give a false Vin # and get some info there :-
DM01