New! 450 R MERCURY

07/03/2019

Mercury 450R Outboard: our first exclusive tests!

As the only French media present at the event, Moteur Boat was able to attend the launch of Mercury's latest flagship. It took place in Nashville, Tennessee, the favorite city of our national Eddy Mitchell! It is the 450R, as in Racing. Barely a veiled response to the 425 hp XTO launched last year by Yamaha, Mercury raises the stakes by adding 25 extra horsepower.

Let's not be mistaken, these are still two outboards with very distinct profiles. The Japanese is a 5.6-liter V8, designed for heavy loads.
The Mercury is also a V8 but with 4.6 liters and, to everyone's surprise, a supercharger like the first generation Verado. A more competition-oriented engine, as its name suggests. It is therefore the same block as the 250-300 hp launched last year, with the supercharger added. The 450R develops 40% more torque compared to the 400R and weighs only 10 kg more.

It allowed us to reach 53.8 knots aboard the Sea Ray 350 SLX-R in twin-engine configuration and 102 knots on an MTI 340 X catamaran also twin-engine… Quite impressive! The Sea Ray thus improves its performance by 7.8 knots compared to the tests we made with the 400R. We made a final outing aboard a Yellowfin 36 open with 3 x 450 hp. Verdict: 71.2 knots top speed and a cruising speed of 40 knots. The fuel efficiency at cruising speed is less impressive than one might think: 0.32 miles per liter.

The 450R will be marketed with the recreational lower unit we know, called “5.44 HD”. Also available will be the Sport Master competition lower unit piercing the surface and designed for boats exceeding 70 knots. The Sport Master features lower water intakes, and a robust 1.25-inch stainless steel propeller shaft.
The curved skeg neutralizes the propeller torque for better performance in single-engine setups. All 450R lower units have a gear ratio of 1.60:1 to prioritize acceleration and speed.

The 450R will be mounted on a Sea Ray 350 SLX-R at the Cannes Yachting Festival from September 10 to 15.