Fond du Lac, WI – High Performance boating enters a new era as Mercury Racing introduces the HP525 EFI sterndrive engine. The all-new engine features custom Edelbrock aluminum cylinder heads, designed exclusively for Mercury Racing, closed cooling, new stainless steel CMI tubular “Sweeper” headers and the exclusive Mercury Propulsion Control Module (PCM) 555. The results? Higher horsepower and a higher torque band throughout the engine operating rpm range.
Multiple improvements to the induction and exhaust system enhance engine-breathing efficiency. Custom Edelbrock/Mercury Racing aluminum cylinder heads, high-flow mono-blade throttle body and flame arrestor combined with longer exhaust runners, provide higher torque than the 500 EFI in the 2500 to 5200 rpm operating range.
The PCM 555 microprocessor enables sequential fuel injection. The microprocessor controls the air/fuel ratio for each cylinder independently for a more consistent and cleaner fuel burn. This results in lower exhaust temperatures for enhanced engine durability. In addition, the PCM 555 optimizes spark timing and knock control for enhanced engine running quality and performance.
An advanced, factory-installed closed-cooling system features five-year coolant for reduced maintenance cost and hassle, as well as increased corrosion protection. The system is used to cool the entire engine cylinder block and aluminum cylinder heads. The multipoint manual water drain system makes winterizing easier. The blue drain plugs on the power steering cooler, headers and fuel cooler are easy to identify and require no tools to remove.
The precision CNC machined, 502-C.I.D. (8.2 L) cylinder block is equipped with heavy-duty performance parts including a forged crankshaft; forged 4340 steel, fully machined and shot-peened Mercury Racing connecting rods; and forged aluminum pistons, designed by Mercury Racing, for maximum strength and durability. High-quality specialty parts are used on the top end as well, including high performance push rods, roller rocker arms, stainless valves and roller lifters. The hydraulic roller camshaft and an idle air valve, located at the rear of the intake plenum, work in concert to improve engine idle quality. A water-cooled fuel system works in concert with a low pressure and high pressure fuel pump to keep fuel temperatures at optimum levels while reducing the potential for vapor lock with today’s fuels. A thermostatically-controlled, high-capacity oil cooler raises engine oil temperatures faster and keeps them more consistent.
The 525 EFI comes equipped with the digital SmartCraft Controller Area Network (CAN) system, a network of sensors that proactively monitor engine functions, which enables the PCM 555 to communicate data to optional SmartCraft SC5000 System View and System Link gauges for real-time data of multiple engine and boat functions.
The SC5000 System View Monitor and accessory System Tachometer calculate fuel flow and range. Additionally, both drive optional single-function analog style
System Link gauges. To accommodate non-SmartCraft installations, the 525 EFI comes with a custom electronic gauge interface module, designed by Mercury Racing, that provides analog gauge outputs.
Standard engine packages come with a 1.36:1 or 1.50:1 gear ratio Bravo One XZ drive in either right-hand or left-hand rotation. The Bravo One XR drive and Mercury Racing Dry-Sump Six drive are available as options as are the new Mercury Racing Integrated Transom System and Bravo One XR Sport Master drives. Modeled after the race-proven Dry-Sump Six drive gearcase and designed for boats capable of reaching speeds in excess of 90 mph, the Bravo One XR Sport Master features a Precision CNC machined, satin-finished aluminum housing. The new gearcase, available in standard and short shaft models, features a parabolic-shaped torpedo, which reduces drag and increases blowout. The four-slot, low-water pickup design reduces the ingestion of weeds and other debris. Standard and short shaft Bravo One XR Sport Master drives enhance overall boat performance in select applications.