300R

The 300R FourStroke is the highest performing engine in its class. The naturally aspirated 4.6L V-8  provides an astounding 44% in increased displacement and up to 40% higher overall bottom end torque than the legacy two-stroke 300XS it replaces.  Custom Racing  intake cam profiles and short intake manifold runners maximize power throughout the rated speed range. An integrated oil cooler keeps oil temps down throughout the Racing exclusive 5800-6400 rpm operating range.

Transient spark calibration boosts torque by 7% for unmatched acceleration. Advanced Range Optimization automatically adjusts fuel delivery for up to 10% improvement in cruise-speed fuel efficiency.

All of this on 87-octane (90 RON) pump fuel while maintaining a comparable weight as it’s legacy two-stroke cousin. Best of all, the  300R is backed by a three-year factory warranty.

Photo of 300R

MODEL DETAILS

The 300R FourStroke is the highest performing engine in its class. The naturally aspirated 4.6L V-8  provides an astounding 44% in increased displacement and up to 40% higher overall bottom end torque than the legacy two-stroke 300XS it replaces.  Custom Racing  intake cam profiles and short intake manifold runners maximize power throughout the rated speed range. An integrated oil cooler keeps oil temps down throughout the Racing exclusive 5800-6400 rpm operating range.

Transient spark calibration boosts torque by 7% for unmatched acceleration. Advanced Range Optimization automatically adjusts fuel delivery for up to 10% improvement in cruise-speed fuel efficiency.

All of this on 87-octane (90 RON) pump fuel while maintaining a comparable weight as it’s legacy two-stroke cousin. Best of all, the  300R is backed by a three-year factory warranty.

Specifications

  • Rated Horsepower (HP/kW)
    300/224
  • Bore & Stroke (IN/MM)
    3.6 X 3.4/92 x 86
  • Idle RPM
    600
FULL SPECS
CATALOG VIDEO
  • Cylinders/Engine Configuration
    V-8 (64 degree) with 32-valve Dual Overhead Cam (DOHC)
  • Displacement (Liter/CID)
    4.6/279
  • Induction System
    Custom Racing Short-Runner Intake Manifold
  • Fuel System
    Electronic Fuel Injection (EFI) Computer Controlled with Advanced Range Optimization
  • Fuel Requirements
    Unleaded Regular 87 Octane Minimum (R+M/2) or 90 RON 10% Ethanol Maximum
  • Ignition System
    SmartCraft PCM 112 Digital Inductive
  • Charging System
    85-amp (1071 Watt) with idle Charge
  • Starting
    Electric Start with SmartStart Protection
  • Lubrication system
    Integrated wet sump
  • Oil Requirement
    NMMA Certified FCW SAE 10W-30
  • Throttle and Shift Controls
    Mechanical and Digital Throttle and Shift (DTS)
  • Tri-Ram Midsection
    High-Durometer Elastomer Upper Mount and Solid Lower Mounts
  • Heavy Duty Midsection
    Solid Mounts; Remote Trim System
  • Gearcase
    Torque Master, Sport Master or 5.44" HD
  • Gear Ratio
    1.75:1
  • Cambered Skeg
    Sport Master and Torque Master
  • Gear Shift
    F-N-R
  • Dry Weight (lbs./kg)
  • L - 20"
    Std: 512/232; HD: 546/247
  • XL - 25"
    556/252
  • XXL - 30"
    566/257
  • Warranty
    3-Year Warranty
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High Performance Marine Engines