Supercharged outboard from Mercury Racing delivers 450 hp from a 4.6-Liter V8 architecture. The race for power never ends…
It reminds me of what Audi, BMW and Mercedes are doing with sport sedans and SUVs: the power of their top-end sporty versions is climbing up and up, in a neverending race for being number one. Some months ago Yamaha released their 425 hp V8 motor, and here’s the response from Mercury: the new Mercury Racing 450R. The power is…well, you can guess. Beside having 50 hp more than the 400R, the new unit states 40 percent higher torque than the sibling. And claiming to be 140 Kg (>300 lbs) lighter on the scale than the nearest competitor, it is indeed a leader in terms of power-to-weight and efficiency.
Not just a tune-up
The 450R is based on the same 4.6-liter V8 block used for the normally aspirated Mercury Racing 300R outboards. The aluminum cylinder heads feature a Mercury Racing Quad Cam Four Valve (QC4) design and double overhead camshafts (DOHC). The valve train features a high-performance intake cam profile and race-spec Inconel exhaust valves. The camshafts are chain-driven and run in an oil bath so there is no timing belt to maintain.
A 2.4-liter belt-driven twin-screw supercharger delivers the extra pressure with zero lag (compared to a turbocharger) for quick throttle response. The supercharger is water-cooled to reduce the temperature of the intake charge and avoid power losses. Twin intercoolers reduce the temperature of the compressed intake charge to further increase air density and – again – avoid power losses. A custom designed intake attenuator is tuned to cancel the harshest high-frequency supercharger noise.
Electronics and other engine components of the Mercury Racing 450R are designed and positioned to create a tight package so that the engine uses the same cowl as the 300R while incorporating higher flow intake vents. Like all Mercury Racing outboards, the 450R accommodates 66 cm (26 in) center-to-center mounting on multi-engine transoms, perfect for maximizing transom space and have as many outboards as your boat can fit (I’m sure in USA we’ll soon see seven or eight…).
At 313 Kgs (689 lbs), the Mercury Racing 450R claims the best power-to-weight ratio for outboards rated 400 horsepower and above. The wide-open throttle (WOT) operating range extends from 5800-6400 rpm, and is complemented with Mercury Racing propellers to optimize acceleration, efficiency, and top speed.
Different from the Mercury standard one, the Mercury Racing so-called Advanced MidSection (AMS) features heavy-duty stainless steel guide plates and stiffened engine mounts that stabilize the outboard and enhance high-speed handling. An optional rear tie-bar bracket integral to the AMS provides a strong and light mounting point and uncluttered installation for catamaran and other high-speed applications. The AMS also isolates the powerhead from the transom to provide a smooth and quiet run. Electro-hydraulic power steering is standard.
Another cool feature (given the potential application of these engines) comes from the 115-amp alternator: it is a match for extreme audio systems and power-hungry electronics, because when the Idle Charge battery-management system senses low battery voltage it automatically increases engine idle rpm to boost alternator output until batteries are charged to the proper level.
The surface-piercing Sport Master gearcase, designed for boats capable of speeds in excess of 85 mph, features low water pick-ups and a crescent leading-edge for maximized efficiency, and for the 450R application, a stout new one-piece 3.2 cm (1.25-inch) diameter stainless steel propshaft. From single-engine performance runabouts to multi-engine catamaran sport boats the Sport Master – in the correct application – will enhance boat handling, speed and efficiency. The available cambered skeg counteracts prop torque for improved performance and handling in single-engine applications. The 450R is also available with the 5.44 HD gearcase for lower-speed and traditional submerged applications. All 450R gearcases have a 1.60:1 gear ratio for enhanced acceleration and speed.
What about propellers? On the new Mercury Racing 450R models the well known MAX5 and Outboard CNC Cleaver props are required for use with the surface piercing Sport Master gearcase. For 5.44 HP gearcase applications, Mercury Racing’s Bravo I FS, Bravo I LT, Enertia ECO XP, and Rev 4 XP are the suggested options.
The 450R is compatible with Mercury Racing Zero Effort Digital controls or any Mercury Marine digital control system, which can throttle up to six outboards with a single lever in some applications (can this mean 12 motors with two levers…? Never say never). Digital throttle and shift technology are standard, while Joystick Piloting for Outboards (JPO) is available for boats rigged with two to six outboards.
The Mercury Racing 450R is compatible with VesselView, which can simultaneously monitor revs, speed, fuel flow and efficiency, temperature, trim and more on up to six outboards on a seven or nine-inch touchscreen display. VesselView also enables Advanced Sound Control, a dual muffler system that can be toggled between a quiet mode and a deep sport tone with a stirring growl on start-up.
The 450R outboard is backed by a three-year limited factory warranty and a three-year limited corrosion warranty. But you can extend that coverage for up to five additional years with a Mercury Product Protection factory-backed extended service plan.
As for the colors, it will be available in Cold Fusion white and the usual Mercury Phantom Black. Cold Fusion White models are finished with Devil Red Eye cowl accent panels and white mid section and gearcase. Black models are finished with Graphite Grey cowl accent panels and matching Graphite Grey mid section and gearcase. More panel kits are available to custom-match the engine to a boat color scheme.
We’ll see the new Mercury Racing 450R in its first installation on a special edition Sea Ray Slx-R 350 Outboard (pictured above).