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For 2003, Mercury is enhancing the cylinder head designs and electronic controls for its Optimax line. It's also introducing the most powerful Optimax ever, the 250XS, a fuel-injected 3.0-liter V-6 developed by Mercury Racing. It features heavy-duty racing-derived solid engine mounts, a hydrodynamically optimized gear case with heavy-duty prop shaft, and high-performance cylinder liners. The 250XS is covered by Mercury's two-year factory warranty and three-year corrosion warranty.

In the four-stroke arena, Mercury's 225-hp EFI, based on a Yamaha engine, is a 583-pound (dry) V-6 with four valves per cylinder, dual overhead camshafts, a 45-amp alternator, and a three-year limited factory and corrosion warranty. Both this engine and the 250XS use Mercury's proprietary SmartCraft bus system to provide the driver with fuel flow data; fuel consumption rates; estimated range; air, water, and engine temperatures; charging level; speed; and even maintenance and service advice.

The 225 also has Mercury's Digital Throttle and Shift (DTS) system, which utilizes SmartCraft technology to eliminate the mechanical cables that operate throttle and shift mechanisms. Instead, the DTS control box connects to the engine's PCM555 (Smart Craft) computer via a single data cable that carries the interpreted signals to small stepper motors, which operate the shift mechanism and throttle body. According to Mercury, the result is smoother shifting, quicker throttle response, and more precise throttle settings. Phone: (920) 929-5000. www.mercurymarine.com.

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