Mercury Racing 500R Outboard

Supercharged power for a variety of boats.

Move the throttle lever, and ­Mercury Racing’s 500R outboard crushes you into the seat or bolster. There’s torque to spare all the way to its max-rated 6,600 rpm. It proved a blast testing aboard various boat types, from pontoons to center-consoles to high-performance catamarans. The 500R’s supercharged whine will appeal to serious speed and power devotees.

This 4.6-liter V-8 delivers this visceral experience thanks to its supercharger. Belt-driven, the supercharger forces more air into the engine, resulting in more torque and power. ­Mercury Racing says it delivers 10 percent more torque than the 450R, which it replaces, and it increases boost pressure by 26 percent.

The 500R also boasts many technological innovations. For instance, a humidity sensor monitors intake air. This allows the engine ECM to combine humidity, air-pressure and air-temperature data to determine the ideal spark timing. It is the first marine engine with humidity compensation.

Quad Mercury Racing 500R outboards
Mercury Racing’s 500R is available in shaft lengths up to 35 inches, and it can be mounted on 26-inch centers. Courtesy Mercury Marine

Mercury Racing claims that 30 more horsepower is made available in high humidity thanks to this technology.

I’ll note here that none of the test boats were dialed in yet. Mounting heights, propellers, etc., had not yet been optimized. As such, Boating’s certified test results will appear in the coming months.

The 500R’s new midsection, called the Advanced Racing Core (ARC), includes a stronger transom plate with 3 inches of vertical adjustment via seven mounting holes, twice the adjustment range of the 450R. An enhanced trim system features two primary hydraulic rams, plus two new booster rams for added trim authority. Slowed trim speed permits more precise trim adjustment at high speeds. Precision-fitted, heavy-duty guide plates and stiffened engine mounts stabilize the engine, ­enhancing handling.

The 500R’s new, more durable 5.9-inch-diameter gear case, called the R-Drive, comes in two versions. Each features a crescent leading edge and fits 17-inch-diameter propellers.

Both R-Drive variants offer low-water pickups; a torpedo shape to thrive in submerged, transition (semi-surfacing) and full-surfacing applications; and a 1.60-to-1 gear ratio. A new intermediate spray plate reduces drag in submerged and transition applications. An adjustable nose-cap pickup system optimizes cooling water flow for submerged and transition applications, and for fully surfaced, ultra-high-speed vessels. A new water pump increases cooling capacity by 57 percent. Compared to the 450R, drive shafts increased to 1 inch from 7/8 inch, and the prop-shaft diameter increased to 1.5 inches from 1.25 inches.

Read Next: Testing the New Mercury Racing 300R Outboard

Mercury Racing 500R outboard gear case
Two gear case options are available. Courtesy Mercury Marine

The base R-Drive is designed for boats capable of speeds between 85 and 100 mph, beyond the speed range of the Mercury Racing 5.44 HD gear case. Many high-speed center-­console boats fall into this ­category. The R-Drive gear case is offered with left- or right-hand camber to balance steering force with standard and counter-rotation props.

The R-Drive Sport is for ultra-­high-speed surfacing applications, primarily high-­performance catamarans and center-consoles capable of 100-plus mph. It features a longer skeg, allowing steering control while fully surfaced at high mounting heights. The R-Drive Sport skeg is available with no camber or with a right-hand camber for single-engine boats. The variant’s prop shaft is made from an ultra-high-strength aerospace stainless-steel alloy similar to that of the Mercury Racing M6 and M8 sterndrive prop shafts. The crankshaft, rods, bearings and pistons have also been updated.

Weighing about 720 pounds, Mercury Racing’s 500R is available in shaft lengths up to 35 inches. It can be mounted on 26-inch centers. Choose between Phantom Black or Cold Fusion White. It comes with a three-year warranty.

Suggested retail on the 500R is $72,000 to $84,500. Color, shaft length, gear case and application impact the pricing. For more information, visit