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.
20, 25, or 30
SHAFT LENGTH
Standard or Heavy Duty
TRIM SYSTEM
Standard, Heavy Duty or Racing AMS
MID SECTION
Camber or Straight
SKEG
3-Year²
WARRANTY
3.6 x 3.4 IN/92 x 86 MM
BORE & STROKE
Custom Racing Short-Runner Intake Manifold
INDUCTION SYSTEM
Unleaded Regular 87 Octane Minimum (R+M/2) Or 91 RON 10% Ethanol Maximum
FUEL REQUIREMENT
Electronic Fuel Injection (EFI) Computer Controlled With Advanced Range Optimization
FUEL SYSTEM
Digital Inductive
IGNITION SYSTEM
115 (AMS) / 85 (CMS)
CHARGING
Yes
IDLE CHARGE
Electric Start With SmartStart Protection
STARTING
NMMA Certified FCW SAE 10W-30
OIL REQUIREMENT
N (CMS), Optional (AMS)
JPO OPTION
DTS (AMS), DTS or Mechanical (CMS)
THROTTLE & SHIFT CONTROLS
Torque Master, Sport Master or 5.44 HD
GEARCASE
1.85 (AMS), 1.75:1 (CMS) or 1.60:1 (CMS, AMS)
GEAR RATIO
512 LBS
DRY WEIGHT
3
CARB STAR RATING
26
MINIMUM CENTERLINE MOUNTING DISTANCE (IN)
Electro-Hydraulic Power Steering
STEERING
Integrated (AMS), Bracket (CMS)
TIE BAR OPTION
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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.
20, 25, or 30
SHAFT LENGTH
Standard or Heavy Duty
TRIM SYSTEM
Standard, Heavy Duty or Racing AMS
MID SECTION
Camber or Straight
SKEG
3-Year²
WARRANTY
3.6 x 3.4 IN/92 x 86 MM
BORE & STROKE
Custom Racing Short-Runner Intake Manifold
INDUCTION SYSTEM
Unleaded Regular 87 Octane Minimum (R+M/2) Or 91 RON 10% Ethanol Maximum
FUEL REQUIREMENT
Electronic Fuel Injection (EFI) Computer Controlled With Advanced Range Optimization
FUEL SYSTEM
Digital Inductive
IGNITION SYSTEM
115 (AMS) / 85 (CMS)
CHARGING
Yes
IDLE CHARGE
Electric Start With SmartStart Protection
STARTING
NMMA Certified FCW SAE 10W-30
OIL REQUIREMENT
N (CMS), Optional (AMS)
JPO OPTION
DTS (AMS), DTS or Mechanical (CMS)
THROTTLE & SHIFT CONTROLS
Torque Master, Sport Master or 5.44 HD
GEARCASE
1.85 (AMS), 1.75:1 (CMS) or 1.60:1 (CMS, AMS)
GEAR RATIO
512 LBS
DRY WEIGHT
3
CARB STAR RATING
26
MINIMUM CENTERLINE MOUNTING DISTANCE (IN)
Electro-Hydraulic Power Steering
STEERING
Integrated (AMS), Bracket (CMS)
TIE BAR OPTION
All prices reflect MSRP in U.S. dollars and are applicable in the US only. Dealer sets the actual price. Pricing does not Include dealer preparation fees, taxes, registration fees, that may apply. See participating dealer for details.
1. Choose Your Colors
Phantom Black
Cold Fusion White
Devil Eye Red
Carbon Fiber
Graphite Grey
2. Choose A Gear Cases
The Torque Master gearcase is designed for heavier boats capable of hitting the 85 mph mark and features a heavy-duty 19-spline stainless steel propshaft.
The surface piercing Sport Master gearcase delivers race-proven performance for boats capable of speeds exceeding 85 mph, with low water pick-ups and a crescent leading edge to maximize efficiency and speed.
The 5.44'' Offshore HD gearcase was designed for submerged applications in the most demanding offshore environments and features a larger 5.44'' diameter torpedo that provides extra lift for heavier boats.
3. Choose A Midsection
The HD CMS features heavy-duty forged transom brackets and a robust single-ram trim system with a remote pump, and optional rear tie-bar mounting plates and side steering brackets.
The durable Mercury Racing CMS for 20-inch models features the integral Tri-Ram trim system.
Mercury Racing Advanced MidSection (Racing AMS) features heavy-duty guide plates, Digital Throttle and Shift (DTS) control and Mercury electro-hydraulic power steering, and optional integrated rear tie-bar brackets and Joystick Piloting for Outboards (JPO).
Mercury Racing Advanced MidSection (Racing AMS) features heavy-duty guide plates, Digital Throttle and Shift (DTS) control and Mercury electro-hydraulic power steering, and optional integrated rear tie-bar brackets and Joystick Piloting for Outboards (JPO).
4. Choose Your Performance Package
Select HD CMS models are available with optional rear tie-bar mounting plates and side steering brackets for high speed applications when using the Sport Master gearcase.
An optional rear tie-bar bracket integral to the Racing AMS provides a strong, ultra-light mounting point for precision steering in ultra-high-speed applications.
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