Mercury Racing 850/1025/1075/1200 SCI Whipple Stage 4 Performance Kit

MERCURY RACING 850/1025/1075/1200 SCI
WHIPPLE STAGE 4 PERFORMANCE KIT

The Whipple Stage 4 Performance Kit for compatible Mercury Racing 850 SCI, 1025 SCI, 1075 SCI, and 1200 SCI applications is a complete high-output upgrade package built around Whipple's latest twin-screw supercharger design. This Stage 4 system replaces the stock 2.3L superchargers with dual 2.9L twin-screw superchargers that are over 26% larger than stock.

The larger 2.9L compressors are designed to turn at lower RPM for reduced heat generation and lower power consumption while providing significantly more airflow and power capacity. For customers upgrading during a rebuild or major performance refresh, the Stage 4 package provides a broad upgrade path for compatible Mercury Racing supercharged applications.

The Stage 4 kit also includes a high-performance PCM calibration, higher lift and more aggressive duration camshaft, Isky tool room valve springs, keepers, HD 12-rib belt, billet spring-loaded belt tensioner, billet front tensioner plate, larger diameter supercharger pulleys, and supporting hardware for a more reliable and adjustable belt system.

On 1075 SCI applications, the Stage 4 package is listed to increase output by 150-175 HP over stock, with an additional 100 lb-ft of torque to help improve acceleration. 850 SCI and 1025 SCI packages are listed to gain significantly more, depending on the application and complete setup. The factory RPM limit is raised from 6200 RPM to 6800 RPM, giving customers a wider propping range and additional top-speed potential when the boat, prop, conditions, and complete setup support it.

Stage 4 Kit Features

• Stage 4 performance upgrade kit for compatible Mercury Racing 850 SCI, 1025 SCI, 1075 SCI, and 1200 SCI applications
• Dual 2.9L twin-screw superchargers
• 2.9L superchargers are over 26% larger than the stock 2.3L superchargers
• High-performance PCM calibration
• Higher lift and more aggressive duration camshaft
• Isky tool room valve springs
• Valve spring keepers
• HD 12-rib belt
• Billet spring-loaded belt tensioner
• Billet front tensioner plate for user adjustment
• Larger diameter supercharger pulleys for increased belt contact surface
• Listed 150-175 HP increase over stock on 1075 SCI applications under Whipple test conditions
• Listed additional 100 lb-ft of torque on 1075 SCI applications under Whipple test conditions
• 850 SCI and 1025 SCI packages are listed to gain significantly more, depending on application and setup
• Listed MPH gains of 7-15 mph, depending on boat setup and conditions
• Increased horsepower for improved top-speed potential
• Increased low-speed torque to help reduce plane time
• Increased low, mid, and high-speed torque for improved acceleration and throttle response
• Increased spark at low and mid speeds for improved engine efficiency
• 6800 RPM limit compared to stock 6200 RPM limit
• Designed for 91 octane fuel using the (R+M)/2 rating method
• Maintains stock-style idle, starting, and driveability

Calibration Service Process

The PCM must be removed and sent to Whipple Superchargers for calibration service. Include a copy of the receipt and any relevant engine, boat, fuel, prop, PCM, supercharger, pulley, belt-drive, camshaft, valve spring, and setup details with the PCM. Typical turnaround time is 7-10 days.

New PCM units may be available upon request. Verify PCM compatibility, engine model, fuel octane, current calibration, supercharger configuration, belt-drive setup, camshaft requirements, valve spring requirements, and complete installation requirements before ordering.

Performance note: Power levels can vary from engine to engine. Boat speed, plane time, acceleration, RPM, and MPH results depend on boat design, propping, atmospheric conditions, operating environment, driver input, and the complete engine package. MPH gains are helpful reference points and are not guaranteed.

Application note: This is a performance kit with calibration and hardware components. It does not diagnose or repair mechanical, fuel system, ignition, sensor, belt-drive, valve train, camshaft installation, supercharger installation, or general running issues.