
Mercury Racing last week unveiled its latest outboard power plant, the 450-hp 450R, which now is the most powerful outboard in the engine builder’s stable. Based on Mercury Marine’s 4.6-liter V-8 block, the new engine also has the highest power-to-weight ratio of any outboard in the industry rated at more than 400 horsepower, weighing in at a comparatively diminutive 689 pounds.
Mercury tapped its high-performance Mercury Racing team to produce the engine, which used its supercharging prowess to bolster the outboard’s output, torque rating and throttle response, among other improvements.
According to a Mercury Racing press release, the 450R uses a “2.4-liter belt-driven twin-screw supercharger delivers pressure charging with zero lag for instant throttle response. The supercharger is water-cooled to reduce the temperature of the intake charge and increase power. Twin charge-air coolers engineered by Mercury Racing reduce the temperature of the compressed intake charge to further increase air density and power output.”

The engines are available with two gearcase options—one for boats that go faster than 85 mph and one for “normal” use—a number of color schemes, and of course, the ability to run Mercury Racing’s full catalog of performance propellers. The engines work with Mercury’s Joystick Piloting system for use with up to six engines. Each engine carries a three-year warranty and will run on octane fuel.
For all the juicy, high-horsepower details, visit Mercury Racing’s 450R website.