Theoreticaly, how mutch hp and or torque will you gain by dropping your intake air per degree? Say in a 300 hp 12 valve.

I am have a Cummins factory re-man marine 12 valve. And I am contemplating running 50 degree see water threw the after cooler insted of 100 degree coolant comming from the keel cooler. The cooler has a zink and is rated for sea water.

 

Don't know about the HP gain, but I would think you would see an EGT reduction.

 

You would probably see minimal HP gain, but would clean-up exhaust.