From the Bank’s Site:

Banks legendary performance reputation was first earned in the high-performance marine engine business in the ’60s’. Since that time world, national, state, and local speed and endurance records have all fallen to Banks Marine engine-equipped boats.

Now, applying the same engineering expertise that motivates the 1,200-horsepower Duramax 6.6L V-8 in their record-setting drag racing, and land speed record competition vehicles, Banks Marine has built the ultimate, fully-marinized, GMC factory-authorized version. Compact and muscular, this twin-turbo engine combines V-8 power and packaging in a design that packs more outright efficiency into every pound and every square foot of engine bay than any “old school” engine.

SPECIFICATIONS:
Engine Displacement 6.6 L [403 in3]
Number of Cylinders 8
Rated Speed (varies) 3000-3800 rpm
Rated Power (varies) 350-575 hp [261-429 kW]
Fuel System Bosch high pressure common rail
Engine Management Banks AutoMind®
Aspiration Turbocharged, seawater after-cooled
Electrical System 12V
Cooling System Closed cooling, belt driven seawater pump
Exhaust System Fresh water-cooled manifolds and risers
Turbochargers Fresh water-cooled turbine housings
Lube Oil System Gear driven wet sump
Duty Cycle Various ratings available
Variations of engine build Work, Sport, High-Performance, Government Service

Video uploaded by U Tube user 

Gale Banks Marine Site Go fishing