• Mercury Racing Reveals QC4v 860 Sterndrive

    860 Horsepower 9.0-Liter V8 with Luxury Car-Like Driveability

    FOND DU LAC, Wis. (Feb. 16, 2017) – Mercury Racing revealed its new QC4v (quad cam four valve) 860 sterndrive this evening at the Mercury Marine Miami International Boat Show media conference. The sterndrive makes its public debut Thursday, Feb. 16, with a 10:15 a.m. (EST) scheduled unveiling in the Mercury Marine booth.

    Designed, developed and manufactured in-house, the naturally aspirated, 9.0-liter engine features Mercury Racing’s exclusive aluminum four-valve cylinder heads and dual overhead camshaft valve train. These quad cam, four-valve heads are integrated with Racing’s proprietary V-8 cylinder block, packed with Mercury Racing-designed and specified hardware. This proven valve train, which greatly enhances engine performance and durability over a standard two-valve design, enables the engine to produce 860 hp at 6800 rpm on 89 octane (Rec 90) pump fuel. The engine’s 6300-6800 rpm operating range offers unsurpassed acceleration for its power rating. The higher rev limits expand the range of propeller options available for a variety of applications.

    Mercury Digital Throttle & Shift (DTS) technology, standard on the 860, provides luxury-car-like drivability. The DTS system also features one-touch Smart Start, automatic throttle synchronization and shadow mode for multiple-engine applications. Mercury Racing DTS Zero Effort controls provide an intuitive control experience – precisely signaling driver intent.

    Legacy DNA

    Racing’s QCV4v family now features models ranging from 860 hp to an astounding 1750 hp! The naturally aspirated 860 shares all the high-performance running qualities of its turbocharged siblings.

    Naturally Wired

    A custom intake system provides the 860 with maximum airflow. Twin 92 mm electronic throttle bodies feed the intake with runners designed to optimize torque.

    Rear-facing ram horn intakes direct induction noise rearward to reduce cockpit noise and enhance engine power.

    • Noise reduction in the cockpit for a more pleasant boating experience
    • Allows for tighter installation of staggered engines due to enhanced exhaust routing

    New camshafts, exclusive to the 860, feature custom lobes for greater valve lift. This, combined with high-velocity cylinder head intake ports, provides maximum air flow to the combustion chamber. New pistons, designed exclusively for the naturally aspirated engine, respond to the fuel/air charge with an efficient 9.75:1 compression ratio.

    The Mercury Racing-designed oil pan features dedicated baffling and a custom windage tray. That, combined with an engine-mounted oil pump, keeps oil away from the crankshaft, virtually eliminating parasitic power loss. Rigging and installation is also facilitated by not having a remote mounted oil sump.

    Engine temps are kept at bay with an all-new, race-proven heat exchanger. Engine oil and glycol for the closed cooling system are routed around the engine via a series of tubes. The tubes are encapsulated in a casting filled with sea water, which serves as a coolant. The heat exchanger provides a higher sea water flow rate for enhanced cooling.

    Power to the Water

    Mercury Racing designed an all-new hydraulic transmission specifically for the 860. Racing developed the new transmission to handle high torque and power levels, and to endure treacherous offshore duty cycles. At the same time, the transmission delivers smooth and consistent shifts, thanks to Mercury’s DTS technology. The compact design also minimizes overall engine package length in both drive-line and close couple installations.

    The 860 comes standard with the legendary Mercury Racing M6 surface drive. The higher capacity M8 sterndrive is optional. The 860’s 6,800 rpm rev limit offers rapid acceleration via Mercury Racing Pro Finish 5 & 6-blade CNC sterndrive Cleaver propellers.

    Below Water Exhaust Option
    In addition to the rear-facing ram horn intakes, 860 owners have an additional option when it comes to reducing engine noise. The 860 can also be configured with the exhaust outlets routed below water for reduced off-plane noise.

    Dressed to Thrill

    The 860 features black powder-coated headers with color matched pulleys. A total of 12 color options are available for the engine, transom and drive.


    The 860 is covered by an unprecedented two years of factory warranty.

    About Mercury Racing

    Based in Fond du Lac, Wis., Mercury Racing, a division of Mercury Marine, is a leading provider of high-performance marine propulsion systems for discriminating boaters worldwide, offering an exciting and fulfilling power boating experience on the water. Using leading-edge technology, Mercury Racing produces high-performance outboards, sterndrives, propellers, parts and accessories. Mercury Racing also produces crate engines for the automotive aftermarket industry. Mercury Marine is a division of Brunswick Corp. (NYSE: BC), the world’s leading manufacturer of recreational products, including pleasure boats, marine engines, fitness equipment, and billiards.
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