Mercury 300 HP Racing V8 Outboard Engine with Electro-Hydraulic Steering, Trim, Tilt, and Long Shaft

The Mercury Racing 300 L is a 4-stroke outboard marine engine designed for high-speed performance boats, race boats, and offshore sport boats that require a long shaft. It features 300 HP / 224 kW and a 4600 cc V8 (8 Cylinder) engine. The Racing series is Mercury's high-performance focused outboard engine group. Maximum power and speed are achieved through a naturally aspirated high-performance engine and Racing ECU calibration.

Racing 300 L Series Features and Technology Advantages

High-performance ECU calibration extends the optimum power band compared to standard FourStroke engines. Precise maneuver control at high speeds is ensured with AMS electro-hydraulic steering.

• V8 (8 Cylinder) Engine (4600 cc): High-performance ECU calibration extends the optimum power band compared to standard FourStroke engines
• Long Shaft (508 mm (20")): Propeller operates at optimum depth at the correct transom height
• High-Performance ECU: Extended power band with Racing calibration
• Electric Start: Instant activation with key or button — comfortable and fast starting
• Power Trim & Tilt: Adjust trim angle with a button during cruising — fuel efficiency optimization; fully raise the engine with tilt
• External Fuel System with Float: Large capacity external tank connection — range determined by user needs

Long Shaft — Which Boat Type Is It Suitable For?

The long shaft (508 mm (20")) is suitable for most inflatable boat, aluminum, and fiberglass boat models. For boats with a transom height of 381 mm, a short shaft model should be preferred.

Technical Specifications

Who Is This Engine For?

• High-speed performance boats: Maximum speed with Racing performance configuration
• Offshore racing and sport boats: Precise maneuverability at high speeds with AMS electro-hydraulic system
• Multi-engine speed-focused configuration: Coordinated power with DTS synchronization
• Speed record and sport performance goals: Mercury Racing engineering

Maintenance and Longevity

4-stroke Mercury engines operate trouble-free for many years with regular oil changes and end-of-season maintenance protocols. The impeller of the water-cooled system should be checked every 100 hours or every two seasons. In saltwater use, freshwater flushing is mandatory after each use.

Related maintenance categories: Maintenance Kit | Engine Oil | Impeller | Mercury Spare Parts

Frequently Asked Questions

Which boat type is the Mercury Racing 300 HP engine suitable for?

The Racing series is developed for speed-focused performance boats with 300 HP. It provides maximum performance in offshore race boats, catamarans, and high-speed sport boats. Weight optimization and power density are priorities in this segment.

How does the High-Performance Mercury Racing engine work?

The high-performance ECU uses different injection timing and ignition maps compared to standard FourStroke engines. The power band is optimized for high RPMs.

How is the Racing series maintained?

Racing engines require a special maintenance protocol suitable for high-performance use. Beginning and end-of-season services should be performed at authorized Mercury service centers. Oil quality and change intervals may be more frequent than for standard FourStroke engines.

Which boat and brand models are compatible with the Racing 300 L?

Mercury outboard motors are compatible with many fiberglass, aluminum, and inflatable boat models thanks to their universal transom clamp or transom mounting system. The only criteria are your boat's transom height of 508 mm (20") and the maximum engine power approved by the manufacturer. You can get compatibility confirmation from Clever Marin by sharing your boat model.

Related Products and Categories

• Mercury Outboard Motors
• Mercury Marine Products
• Mercury Spare Parts
• Mercury Racing 150–300 HP
• Mercury Racing 350–500 HP
• Outboard Motors
• Boat Engines
• Maintenance Kit
• Impeller
• Anode

Is This the Right Configuration for Your Boat?

Share your boat model, transom height, and intended use — let's confirm the suitability of the Mercury Racing 300 L engine for your boat and the correct shaft selection together.