Gearcase, control and steering options – plus the expertise of the Mercury Racing team – allow you to configure your 300R outboard for near-custom performance.
300R
Take the lead and never look back with the Mercury Racing 300R outboard.Featuring a rock-solid 15-inch HD Conventional MidSection (HD CMS), this adrenaline-pumpingV8 powerhouse brings modern R-Series four-stroke technology to high-performance sport, flatsand bass boats. Whether you’re replacing a high-output two-stroke or building your new dreammachine, experience the ultimate fusion of breathtaking speed and control.
Trimmed Down. Amped Up.
With a proven offshore pedigree, the HD CMS is built to exceed the most extreme boating demands. Heavy-duty forged transom brackets and a robust single-ram trim system with remote pump keep you running at the highest speeds through the most challenging conditions.
Refined for Bold New Applications
Smaller footprint, same racing DNA—now available for boats that demand agility without sacrificing performance.
- Off Shore Racing
- High-Performance Sports Boats
- High-Performance Bass Fishing
- Competition Drag Racing
Choose Your Configuration
Versatile Steering Setup
Choose from hydraulic or power steering, with optional rear tie-bar mounting plates and side steering brackets.
Premium Controls
Digital Throttle & Shift - smooth, effortless shifting and lightning-fast throttle response. Mechanical - full-feel controls for those who prefer traditional feedback and response.
Gearcase Options
Engineered for versatility, the 300R features two gearcase options tailored for specialized performance.
Compact. Capable. Uncompromising.
The 300R with the 15-inch HD CMS delivers Mercury Racing performance in a smaller, more versatile package. Built for boaters who demand precision handling, aggressive acceleration, and proven reliability. Ready to rig your next high-performance machine?
Specifications
Product details
4.6L V8 300R
Horsepower (HP/KW)
300/224
WOT RPM
5800-6400
Engine type
V8 (32-valve DOHC) Naturally Aspirated Four Stroke
Displacement (LITER/CID)
4.6 / 279
Induction system
Custom Racing Short-Runner Intake Manifold
Fuel requirements
Unleaded 87 Octane Minimum (R+M/2) or 90 RON
Oil requirement
MRX 10W-30 or Mercury 10W-30 Full Synthetic
Charging (AMP/WATT)
115 / 1449 - AMS or 85/1071 - CMS
Throttle & shift
Digital Throttle & Shift (DTS) or Mechanical
Midsection
Heavy Duty Short Mid Section with Solid Mounts; Remote Trim Pump
Gearcase
Torque Master Sport Master
Gearcase ratio
Torque Master: 1.75 Sport Master: 1.60 or 1.75
Dry weight (LB/KG)
545lbs/247kg