I was wondering if I heard correctly that the same engine we have is also used in marine application albet a few different changes. But, puts out a group more HP. Does the marine motor utilize the same fuel pump and if so what was done to it to make it put out more?
Yes, the Cummins 6b is used in marine applications. . see my signature, I have one

The 6b is offered from about 130 hp to 370 hp.
The "older" 6B series engines (mid 80s to early 90s) were popular as a 210 hp (turbocharged) and 250 hp ( sea water aftercooled)... these engines had a Lucas/Cav pump.
The modern 6B series are usually seen as a 6bt (220 hp) to a 6bta (370 hp, sea water aftercooled) , and use a Bosch 7100 series pump.
The engine I have is a 6bta (jacket water or antifreeze aftercooled) and is rated at 270 hp @ 2600 rpm
If you go to the Cummins website you can see all of this and look at hp and torque curves for these engines.
Jay