New V-8 Four-Stroke Outboards: Powerful. Fast. Efficient.

We are excited to debut our all-new 250R and 300R outboards.

The 300R with Heavy Duty midsection and Sport Master gearcase.

Designed, developed and manufactured in-house, the naturally aspirated, 4.6 Liter V-8 four-stroke engines share Mercury Racing’s venerable Quad Cam Four Valve (QC4) sterndrive DNA – complete with aluminum four-valve cylinder heads and dual overhead camshaft (DOHC) valve trains.

The four valve heads and DOHC valve train is integrated with Mercury’s proprietary V-8 cylinder block, packed with high performance hardware. The new platform replaces the two-stroke V-6 250XS and 300XS models.


No Replacement for Displacement

The stout V-8 powerhead provides an astounding 53% increased displacement compared with the 250XS and 44% more displacement than the 300XS resulting in 40% higher overall bottom- end torque compared to the legacy two-strokes.

Advanced Range Optimization automatically adjusts fuel delivery for up to 10% improvement in cruise-speed fuel efficiency.

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 to the legacy two-stroke 250 XS and 300 XS models. Best of all, the new 250R and 300R models are backed by a three-year factory warranty.

Most Versatile Performance Outboards on the Market

Racing exclusive intake cam profile and short intake manifold runners for maximized power throughout the rpm band.

The 300R is highest performing engine in its class. The powerhead features custom Racing intake cam shafts and an exclusive short runner intake manifold. An integrated oil cooler keeps oil temps down throughout the 300R’s higher 5800-6400 rpm operating range.

Factory rear tie-bar models are available for enhanced stability on high speed multiple engine catamaran and offshore center console applications.

The 300R is available with either mechanical or digital control systems.  In addition, two midsection (Tri-Ram and heavy-duty HD) and three gearcase (Sport Master, Torque Master, and 5.44” HD) options ensure compatibility with any boat that needs to go fast.

Factory rear tie-bar models are available for enhanced stability on high speed multiple engine catamaran and offshore center console applications. An optional side steering bracket kit is also available.


The 250R replaces the legacy 250XS OptiMax.

The 250R is available with a mechanical control system. It features the Tri-Ram midsection and the surface piercing Sport Master gearcase. Designed for boats capable of speeds in excess of 85 mph, the Sport Master features low water pick-ups and a crescent leading-edge for maximized efficiency.

Custom Colors

The 300R with optional Graphite Grey accent panel.

An optional Graphite Grey accent panel is available as a kit. A paint-ready kit is also available to custom match the engine to the boat.




Hand Crafted Propellers

A full arsenal of custom Mercury Racing propellers are available to maximize performance in any application

See your local Mercury Racing dealer to Revolutionize your ride with a new Mercury Racing V-8 FourStroke outboard!

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18 thoughts on “New V-8 Four-Stroke Outboards: Powerful. Fast. Efficient.”

  1. How will this compare with my current 2017 Verado 250 Pro for speed and mpg if put on another 21’6” Phx bass boat? Could this motor be used for trolling on occasion?

    1. Hello Sam. As of now – we don’t have performance data comparing the Verado 250 vs. the 250R. The Verado features the Advanced Midsection compared with the 250Rs conventional tri-ram midsection. The 250R is only available with the surface piercing Sport Master gearcase.

  2. I just bought a racing 250xs last month , I’m loving it but I hope I didn’t make a mistake not waiting a bit longer…..

  3. will the 300r run any better with higher octane like 91….
    running on a bass boat what do you recommend? TM lower and what mid section and what control system….currently running a phoenix 721 with 300xs and TM lower boat and motor 2015……fixing to order new 721 and 300r and need some help please….current set up 83 all day long so do I stick with TM or try SM?

    1. Hello Wallace;
      No need for 91-octane with the 300R. It is designed to run on 87 octane. 91 octane won’t help it a bit in terms of performance. If your 300XS with the Torque Master is running 83 today – then you may want to consider running the Sport Master which s designed for speeds in excess of 85 MPH. It depends on the hull. Does it have natural bow lift – or do you need to use trim to get the bow up for top speed? If it lifts naturally – then the surfacing Sport Master may be the ticket. The 300R packs quite a bit more power than the 300XS. You should check with Phoenix to see if they have ever installed Sport Master engines on any of their hulls. I know Bullet bass boats have been rigged both ways – Torque Master ProXS and Sport Master XS engines. You will wan to go with the Tri-Ram mid-section.

  4. Hi Rick

    I have a 300R 1.75L SM HD Camber on order.
    I need to know the remote trim pump up and down pressures and
    flow volume. Also the size of the lines/fittings. So I can get some
    extra long lines that will handle the pressure and flow amount.

    1. Hi Rex. Congratulations on your 300R purchase! I’m checking into the trim line/pump volume for you.

  5. I am looking to order the 250R. Since these motors are so new to the market, it is difficult to find much information on the new line of 4-stroke engines. What is the difference in the new 250 ProXS and the 250R?? Will there be any noticable difference in performance? I am running a Legend Alpha and looking to get away from the old 2-stroke ProXS.

    1. The 250R and 250 ProXS shazre the same powerhead and midsection. The only difference is the gearcase. The ProXS is fitted with the Torque Master. The 250R comes equipped with the surface piercing Sport Master. The Sport Master is designed for use on lighter weight hulls with natural bow lift and capable of speeds in the low 80s. If your boat needs power trim to raise the bow – go with the ProXS. You are going to love the enhanced bottom end torque and acceleration!

  6. Can’t decide…What is the difference between the new 300 Pro XS V8 and the 300R? Would be installing on a bass boat…Please help!

    1. Hello Jeff: There are quite a few differences between the two. Lets start with the powerhead. The 300R turns up an additional 200 rpm (5800-6400). It features an integrated oil cooler to keep things cooler at the higher operating rpm. The 300R has shorter intake runners and a custom intake cam for 40% more bottom end torque when compared to the legacy 300XS 2-stroke it replaces. it also delivers 10% improvement in acceleration over the XS. Back to the comparison between the two – the 300R is a very strong 300 in terms of actual prop shaft horsepower. The ProXS comes with the tri-ram midsection and Torque Master gearcase. The 300R is available with the tri-ram midsection with the Torque Master or our surfacing Sport Master gearcase. We also have the heavy duty midsection models to endure harsh – offshore conditions. HD models are available with Sport Master and the 5.44-inch HD gearcase.

  7. hello
    amazing engine, am looking for more performance and details before picking one ?

    Please who’s should i contact ?

    1. Hello Ali. See your local Mercury dealer or visit our website for full details regarding the 250R and 300R outboards.

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