New 400hp Mercury Race Offshore XCAT engine

Based on the all-new Verado 400R outboard, the much-anticipated new Mercury Racing ROS (Race Offshore) is described by its makers as a potent four-stroke racer. The big new outboard is set to make its imminent debut on November 19 at Round Five of the 2015 XCAT World Series in Dubai, UAE.

As we have noted previously, XCAT has partnered with Mercury Racing in the development of this engine to replace the existing fleet of old-tech Mercury Racing two-stroke 2.5L EFI race outboards that we saw on display at the Gold Coast XCATs racing event in August.

Ronan Morgan, CEO of World Professional Powerboating Association (WPPA), said: "All those involved in the XCAT World Series are looking forward to the introduction of the new Mercury four-stroke engines.

"Not only are these environmentally friendly, they are reliable and provide a huge increase to the horsepower and torque which are essential for an action-packed weekend of racing."

"As promoters of XCAT Racing, the WPPA have had a long-standing relationship with Mercury Racing. We've worked closely together in the testing and development of the engine to provide the ultimate in performance and fan experience."

FOUR OVERTAKES TWO
Mercury Racing General Manager Erik Christiansen said: "We are very excited to launch our new Race Offshore competition outboard. The venerable Mercury 2.5L EFI two-stroke has been a mainstay for many years and is still a solid product. The ROS builds on that foundation while using the four-stroke technology today's market demands."

"We worked with the WPPA to develop a strong, reliable engine that meets the new U.A.E. exhaust emissions requirements. The ROS will be homologated into the Union Internationale Motonautique technical specifications for XCAT.

"Next season will be a transitional year with the entire XCAT field switching to the ROS four-strokes for 2017. I’m looking forward to seeing our new engine compete... in Dubai."

A Sport Master gearcase transfers the ROS’s massive power to the water. And to ensure every revolution counts, Mercury Racing has developed an all-new line of CNC cleaver propellers specifically for the ROS.

Clearly, this isn’t a standard Verado. Mercury says the similarities end at the powerhead...

The AMS midsection is replaced with a billet aluminum housing. Mercury Racing developed the new midsection to lower the overall engine centre of gravity. The 10-inch mid, coupled with the heavy-duty swivel clamp bracket assembly, brings the overall engine mounting height to 15-inches – matching the current 2.5 EFI configurations.

The low CG, combined with solid upper and lower engine mounts, is critical for overall handling at competition speeds, particularly when powering the high-performance catamarans into and out of corners.

The ROS also utilises a remote dry sump system, which holds 8L of Mercury Racing FourStroke Oil, the same semi-synthetic 25W-50 oil used to lubricate and ensure long life in the high output QC4v sterndrive product line.

A lightweight, carbon fiber lower cowl conceals the transition of powerhead to midsection.

Dual rigging tubes facilitate rigging of external systems. To assist in the repower of the fleet, the ROS uses the same high-pressure fuel pump, also mounted in the boat, as the existing two-strokes.

DIGITAL CONTROLS AND TRIM
The ROS brings XCAT into the digital age with Mercury Digital Throttle & Shift (DTS).

DTS replaces traditional throttle and shift cables with digital precision, resulting in smoother shifting and instant throttle response. Mercury Racing’s ergonomic, high-style Zero Effort Digital controls precisely signal driver intent to the DTS-equipped Mercury Racing ROS outboards.

An integral power trim switch in the throttle handle provides fingertip trim control. The DTS system also features one-touch Smart Start and automatic throttle synchronisation.

XCAT GRAPHICS
The Mercury Racing ROS features the XCAT World Series logo and color-matched orange accent graphics. The custom graphics package is featured as a tribute to the series’ exclusivity in Mercury Racing power and their support in product development.

CUSTOM PROPS
With the ROS comes a new line of five-and six-blade CNC Cleaver propellers. The Lab Finished props, featuring a high-performance over-the-hub exhaust design, were developed specifically for surface-piercing applications such as those endured in the rigors of offshore powerboat racing.

The props are rated for 400hp and are available with blade rake angles of 13, 15, 18 or 21 degrees. A variety of pitch sizes are available to dial-in each hull for maximum efficiency and performance.

See the new Mercury ROS in action at Dubai with live online coverage at XCAT Racing.