Direct Diesel replacement of gas V8
 

6.5 Liter block that is used in the military Humvee.

MarineDiesel manufacturers the marine industry’s only diesel engine intended to be a direct replacement for existing gas engines. Why even consider cutting your existing boat hull, or even more extensive hull modifications when you could repower with a MarineDiesel.

MarineDiesel utilizes a custom intercooled supercharging system. This Low Rpm - High Torque Rise system in conjunction with a full 6.5 liters of displacment allows MarineDiesel to achieve the low end performance most inline small displacement diesels find difficult to achieve.

They just inked a deal to provide it as a package with mercruiser

Marine Diesel USA