300R vs 300XS: And the Winner Is?

The business end of 112 mph!

I recently wrote a feature post on Liberator Boats of Florida and their initial experience with our new 4.6L V8 300R FourStroke outboard. I elected to feature Liberator as company owner Randy Corson had just received his first 300R in June. Randy has extensive experience with our V6 300XS two-stroke. I was anxious to get his feedback regarding our new engine and how it compared  with the 300XS it replaced.

Randy provided some initial performance numbers and then compared them with his archival 300XS data:

The 300R Sport Master gearcase features a 5.44 inch diameter torpedo for enhanced durability. The larger case is needed to handle 40% increase in bottom-end torque produced by the 4.6L V8 FourStroke engine.

Both engines featured the Sport Master gearcase. The 300XS had a 1.62:1 gear ratio. The 300R had a 1.75:1 gear ratio.  Due to the gear ratio difference, the 300XS ran a 32-inch pitch propeller. The 300R ran a 34-inch pitch prop. The bare hull weight of the 300XS hull is 940 pounds. Randy said it is the fastest 300XS powered 21-foot Liberator he has ever had.  The bare hull weight of the 300R boat was 1063 pounds.

The CNC outboard cleaver propeller.

“We saw  1.5 to 2 mph faster top-end speeds with the 300R compared to the 300XS with comparable props. At the time, the 300R topped out at 106 mph; that’s 5-6 mph faster than the 300XS when running a 15-1/4-inch diameter – 34-inch pitch Mercury Racing 5-blade CNC outboard cleaver.

Randy ran the CNC cleaver again on Christmas Day and was blown away by the performance – a top speed of 112 mph!

While the top-speed difference is impressive, acceleration is where the 300R really shines. The 300XS accelerates from 40-100 mph in 25 seconds. The 300R boat catapults from 40-100 in 18 seconds! The big difference can be attributed to a 44% advantage in displacement (4.6L vs 3.2L) the 300R has over the 300XS. That results in a 40% increase in bottom-end torque.

While the top-speed difference is impressive, acceleration is where the 300R really shines. The 300XS accelerates from 40-100 mph in 25 seconds. The 300R boat catapults from 40-100 in 18 seconds! The big difference can be attributed to a 44% advantage in displacement (4.6L vs 3.2L) the 300R has over the 300XS. That results in a 40% increase in bottom-end torque.

Hole shot acceleration is exhilarating as well. From 0-20 mph, the 300R is 25% quicker than the 300XS. Mercury’s proprietary transient spark calibration boosts torque by as much as 7% by optimizing spark timing and fueling to assist in superior hole shot performance.

We are excited to see the performance gains people are experiencing with our new 300R in both single and multi-engine applications.

 

 

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