.JPG/v1/fill/w_320,h_320/file.jpg)
The Mercury Racing 2.5 Liter 300 Drag and S3000 are among the most revered high-performance outboard engines in drag boat racing and offshore competition.
Built by Mercury Racing, these engines represent the pinnacle of two-stroke V6 outboard engineering, delivering incredible power-to-weight ratios, precision fuel management, and high RPM capabilities for peak performance.
Key Specifications of the 2.5 EFI Drag (300 Drag)
The Mercury 2.5 EFI Drag is specifically engineered for maximum acceleration and speed in short-distance racing applications. Below are its key technical specifications:
Horsepower: 300 HP
Propshaft Kilowatts: 224 kW
ECU Box Rev Limit: 11,500 RPM
Idle RPM in Forward Gear: 650-750 RPM
Weight: 375 lbs. (170 kg)
Piston Displacement: 153 cubic inches (2.5L / 2507 cc)
Bore & Stroke: 3.50 in. (89 mm) x 2.65 in. (67 mm)
Recommended Spark Plug: NGK-BUZHW (P/N 33-14103550)
Firing Order: 1-2-3-4-5-6
Maximum Timing: 25° BTDC
Idle Speed Pickup Timing: TDC ±2°
Fuel Pressure: 56 psi
Minimum Water Pressure at WOT: 15 psi (Measured at Exhaust Cover)
Gear Ratios: 1.87:1 or 2:1
Recommended Gear Case Oil: Quicksilver Hi-Performance Gear Lube
Gear Case Lubricant Capacity: 22.5 fl. oz. (666 mL)
Battery Rating: Minimum reserve capacity rating of 100 minutes with a CCA of 350
Charging System Output: 16 amps @ 7500 RPM
Transom Height: 15” (381 mm)
This engine is optimized for extreme racing performance, incorporating high-compression pistons, aggressive port timing, and precision-tuned exhaust systems to maximize power output.
Mercury Racing S3000
The S3000 is another variant of the 2.5-liter V6 designed for Formula 1 tunnel boat racing and other high-speed competition applications. This engine, while similar to the 300 Drag, has distinct modifications to suit endurance-style racing.
S3000 vs. 300 Drag: Key Differences
Application-Specific Tuning:
The 300 Drag is optimized for short-distance drag racing, emphasizing acceleration and peak horsepower.
The S3000 is tuned for endurance racing, such as Formula 1 tunnel boat competitions, prioritizing sustained high RPM and fuel efficiency.
Exhaust Tuning:
The 300 Drag features a more aggressive exhaust port timing to extract maximum power in short bursts.
The S3000 utilizes exhaust and cooling modifications to handle extended high-RPM operations.
Rev Limit & RPM Range:
The 300 Drag is electronically limited to 11,500 RPM.
The S3000 typically operates in the 9,500-10,500 RPM range for better reliability in long races.
Gear Case & Lower Unit:
Both engines use high-performance gear cases with optional 1.87:1 or 2:1 gear ratios.
The S3000 may use a SSM #4 gearcase designed for better handling in tunnel boat conditions.
Ignition & ECU Mapping:
Both engines are equipped with high-performance ECU tuning, but the S3000 is optimized for smoother power delivery across extended races.
The 300 Drag has an aggressive fuel and ignition timing map to deliver peak acceleration.
Performance & Applications
300 Drag: King of Acceleration
The 2.5 EFI Drag is a dominant force in drag boat racing, where instant power delivery is the key to winning races. Its lightweight build and high-revving nature allow it to achieve blistering speeds in a short span, making it the top choice for outboard drag racing competitions.
S3000: A Powerhouse for Circuit Racing
On the other hand, the S3000 is designed for Formula 1-style outboard racing, where endurance and handling at high speeds over long distances are crucial. The S3000 is widely used in closed-course tunnel boat racing, where maintaining speed through turns is as important as straight-line acceleration.
Conclusion
Both the Mercury Racing 2.5L 300 Drag and S3000 showcase Mercury Racing's expertise in high-performance outboard engineering. While the 300 Drag is built for all-out acceleration in drag racing, the S3000 is optimized for high-speed endurance racing.
Their legendary power-to-weight ratio, high-revving two-stroke design, and race-proven durability have made them icons in the world of performance outboard racing. Whether you're looking to dominate in a straight-line sprint or excel in circuit racing, these Mercury Racing powerhouses deliver the ultimate edge in competition.
留言