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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65 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…..

      1. Rick
        I have a 21′ Canyon Silhouette with a 1998 Promax 300. I think the boat and motor weigh about 2200 or 2300 pounds. I am considering repowering with either the 300R or the 400R but not sure if the 400 will be to heavy. Which do you think would be best option most of our boating is spent on a small water ski lake but we like to go to Lake Powell and lake Havasu to run fast. Top speed now is about 70 MPH with a Bravo 26 pitch prop. what could I expect for speed. what props do you think? I have a High 5 for skiing and the bravo 1 for speed?

        1. I forgot to add the Canyon is an open bow picklefork modified tunnel and I mistyped the top speed it is 78MPH not 70

        2. Jim,

          Cool boat. It will be hard to be the 300R for what you intend to do with it. It has loads of torque, and runs on 87 octane, versus 91 octane with the 400R. The Bravo I FS would be a great all around prop.


          1. Nick
            I am trying make sure I have the set up correct before I buy the new motor. The motor height it is about 3.5 inches below the bottom of the center sponsion and when I start trimming up the boat starts proposing until I get up over 50 mph. It is mounted on a manual jack plate with 12″ setback. I am running a high 5 for water skiing.
            Any thoughts?

          2. Jim,

            Are you measuring from the prop shaft to the center sponson? If so, that is a very low engine height and will be causing your porpoising. This is definitely compounded by the high five prop, it is not meant to be a 50+ mph prop.


          3. sorry about that yes the center of the prop shaft is 3 1/2 inches below the bottom of the center sponson and it porposes with the Bravo 1
            How much would you suggest i raise the motor?
            thanks for your help

  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.

  8. Hello,
    I just ordered the 300R and a 2019 Phoenix 21PHX. Which pitch prop should I order for top end speed with a decent hole shot. Need is to go over 80 MPH with 2 guys.

    1. Jay,

      What gear case are you going to be running? The Fury has been the prop of choice for the Phoenix, but you may run out of pitch and diameter if you are going to be over 80 mph with a Sport Master gear case. A 29 pitch Bravo I FS will put you well over 80 mph and should have decent hole shot for you as well. Your goal for top end speed should be right around 6250 rpm, that is where the 300R is making peak power.


  9. I just received my 300r on phoenix 721 phx and there wasn’t decal on the back of motor like one in picture. Have you changed the look?

    1. Jim,

      The red accent panel ships with the engine and is installed by your dealer. You will need to contact the dealer that rigged your engine for support.


  10. I have 2-300x (2003) motors on a DCB F26.
    Runs just over 100 and is rigged so it slowly climbs out of the hole cranked and trimmed all the way down.

    300r’s on order supposed to be here in August. I’m hoping they are quieter and can mount one hole lower on transom to get out of the hole better ( don’t really need to go 120..)
    Ideas on new prop pitch/diameter ? Recommendations ?
    Definitely getting digital controls..would be fine w 2 levers I’m thinking ..? Simple

    1. Jamie,

      The new Sport Master is much larger in diameter than the style you are running on the 300X’s, meaning you will at least need to run it at your current height if not higher. Most cats are running the prop shaft 1 3/4″ to 2″ above boat bottom. You will be amazed with hole shot with the 300R’s, the torque is unbelievable. Did you order the 1.60 ratio? The MAX5 ST has been a great prop so far on that hull with 300R power. Compared to the original MAX5, the MAX5 ST comes with a 15.25″ diameter for reduced slip and shortened barrel to reduce stern lift. If you are getting the 1.60 ratio, a 32 pitch set of MAX5 ST will net you 110 mph on the limiter. 34 pitch will be 115-118 mph.

      Thumbs up on the DTS controls, they are a big improvement over mechanical.


        1. Jamie,

          The 1.75 gear ratio will limit your propeller options. If you want to run over 107-108 mph with a 1.75 ratio, you will need to run CNC cleavers. There is a 26 Adrenaline with twin 300Rs (1.75 ratio) in California that ran 108 mph with 34 MAX5 STs on the limiters. He is now switching to cleavers for more speed.


  11. Our 28 Skater that has never seen Ethanol fuel is @ Skater for revised fuel tanks, sponson water notch’s, and minor transom to deck blending. Originally, the boat was rigged with 2.5’s, but in 2006 we sold the 2.5’s and installed a new set of 2005, 300 X, just after the 300 XS came out. Joey Impressia was our mentor for choosing those excellent Legacy engines. On GPS, with Mercury 4 blade x 34, the boat sees 119 mph. So, now you have the 450R and 300 R, forward thinking, while the boat is at Skater, should the transom be hardened, and would CG be an issue with 450 R’s, conversely, your 40 % torque rise on the 300 R Vs 300 XS is interesting—-would that same formula apply to the 300 X with a sum total of 20 hours run time ?

    1. Lloyd,

      Awesome boat. The 300X motors were always considered the holy grail because they punched above their weight class among 300 hp outboards. We have been ecstatic with the performance of the 300R. There are top speed gains across the board compared to legacy product, and the added torque improves hole shot and makes for a much more exciting ride. With the available smooth DTS controls, minimal maintenance, and vastly improved fuel economy (plus 87 octane), technology has come a long way in the last 15 years. I would think the new 300R’s and CNC cleavers would be 125 mph all day for you. The 450’s would be a bit extreme for your boat. Our MTI 340X test boat is over 130 mph with 450s.


      1. Nick,
        We have Marine Machine wing plates and steering rams, though not sure what the package weighs. Do I understand the 300R has integrated hydraulic steering, if so, is a remote pump required ? For embedded wing plates, what do they weigh ? For the speed master, do you have options, such as hardened parts, prop shaft diameter, etc. ? Also, are there mid section options ? What have I forgotten ?

        1. Lloyd,

          The 300R does not have the integrated steering, that is on the 400R and 450R, anything with the advanced mid section (AMS). The 300R only comes with a conventional mid section (CMS). For your application, you would need the cat models, which come with side steer heavy duty wing plates and a rear tie bar system. We include all of the hardware but the steering rams themselves are bought through the after market manufacturer of your choosing (Latham, etc.). The steering system operates on our power steering pumps, which are mounted in the boat. Check out the blog “300R with Integrated Rear Tie-Bar & Side Steer” for the pictures of this setup, it is very impressive. Your gear case would be the 1.60 Sport Master.


    1. Abdullah,

      The engine designed for your setup is the 300R side steer model. The pair comes with heavy duty wing plates and a rear tie bar mount. The model codes are 216A and 217A for the pair when ordering, for the 1.60 gear ratio and mechanical controls.


  12. Hello sir.
    Im currently running 280s on my 24 Skater.
    I love the motors but I am
    Wanting to upgrade to better fuel economy and less maintenance.
    Do you think the 300R is to much weight for the 24 Skater?
    Do you have any test/experience with this engine/boat combination?
    Do you think I will gain or lose speed going from 280s to the new 300Rs?
    Thank You for your time and help,

    1. John,

      To my knowledge, nobody has put 300R’s on the 24 Skater. However, Randy Corson did put them on a 25 Liberator which is a very similar boat. I would be more concerned with transom strength than anything if the boat was designed and built around the 2.5s. There are several 24 Skaters with 300XS’s, the R is almost the same weight. I’m not sure what you are currently running for speed but with the 300Rs you can expect 120+ mph with CNC cleavers and the 1.60 gear ratio.


  13. Nick,
    I have a 24 Skater with twin 280s that I love.
    I am thinking about buying 2, 300Rs for fuel economy, reliability, and less maintenance. Is the 300R a good setup for a 24 Skater? or are they too heavy for the boat?
    Have you guys ran a 24 Skater with twin 300Rs?
    Any input and advice is appreciated.
    Thank you for your time and help,

    1. John,

      To my knowledge, nobody has put 300R’s on the 24 Skater. However, Randy Corson did put them on a 25 Liberator which is a very similar boat. I would be more concerned with transom strength than anything if the boat was designed and built around the 2.5s. There are several 24 Skaters with 300XS’s, the R is almost the same weight. I’m not sure what you are currently running for speed but with the 300Rs you can expect 120+ mph with CNC cleavers and the 1.60 gear ratio.


  14. I recently purchased a new Parker 2300 Big Bay with tunnel hull, the boat weighs in at 2900 lbs. I ordered a 300R with the Torque master gear case and Tri ram mid through my dealer here in Texas and I’m currently waiting on the motor to be delivered. I have several questions for you. What prop do you think that I should start out with to keep me in the proper RPM range? Are all of the options plug and play so that I can add them after the purchase if I forgot to get a certain one? Can I get the extended warranty during the factory warranty period? I think that this motor basically has all of the options as the Pro XS am I correct? My last question is if I ordered just the hydraulic steering can I get the power steering after I have already got the motor and add it. The reason in my decision to purchase the 300R over the Pro XS is the integrated oil cooler and the improved hole shot, I will be spending lots of time in shallower bay systems and I’m hoping that this is the right decision. Thanks

    1. Louis,

      As far as the “options”, your engine has all of the bells and whistles that come with the 300 Pro XS. The key differences are the oil cooler, intake runners, intake cam, and calibration. Ideally, your RPM at wide open throttle should be 6000-6300. For props, I would recommend running something that the dealer has on hand in order to get a base line. Something in the 20 to 22 pitch genre, Tempest, Rev4, Bravo. It will be easier to make a recommendation once you have some baseline data with a propeller. Yes you can add the extended warranty during the first three years of normal warranty. For steering, you normally need to change the helm when adding the power assist (different models), but you can keep your hoses and cylinder. If you are referring to vessel view screens and things of that nature being plug and play, they are very easy to install, they plug right into the junction box behind the dash.


  15. Hello, I’m Massimiliano and I live in Italy .
    I’ d like to know …
    1. Where is it the discharge in mercury V8 300 R sport master gearcase ?
    2. For a single engine skeg must be’ straight or curved?
    3. Is it better a sport master or torque master gearcase in a rubber ” Focchi 730 ” which speed is about 65 knt ?
    4. Which is the difference between sport master and torque master ?
    Best regards

    1. Massimiliiano,

      The drain, or discharge, on the gear case is under the prop shaft. For single engine applications, you will need the cambered (curved) skeg. At your speeds, you would most likely benefit from the Torque Master II gear case, rather than the Sport Master. The Sport Master has a coned design with low water pick ups, making it ideal for surfacing 85+ mph (75+ knt) applications. On most applications less than 85 mph, the Sport Master will actually be slower than the Torque Master II because it has more surface area dragging through the water.


  16. Hello, I am a “very happy” owner of a Mercury v8 300r with sport master gearcase but I have a problem, I can’t raise the bow of my rubber and I don’t know if it’s a propeller problem because I know that the sport master gearcase makes raise the stern.
    So what do you recommend me? Can I solve with an appropriate propeller or I need to mount the 544hd gearcase?
    I have a rubber with a keel V-shaped and it weighs 2800 pounds all incluse and the maximum speed reached was 65 knot.

    1. Massimiliano,

      For a 65 knot setup, you will want the Torque Master gear case. The Sport Master is typically 3-5 knot slower than the Torque Master at speeds under 75 knot. You could be able to exchange the Sport Master for a Torque Master with your dealer.


  17. I am considering ordering a 300R on my new tritoon in lieu of a 350 Verado. Is this the right choice for speed and low to midrange torque when pulling a tube or wakeboard? Is there any notable fuel efficiency difference? Thank you

    1. Jayson,

      Most will run the new 300 Verado on a Tritoon over the 300R. It has the same Advanced Mid Section as the 350 Verado, but features the new V8 powerhead. Torque for watersports and mid range fuel efficiency is much improved, you will not be disappointed.


  18. I am torn between quad V8 300hp Verado and the V8 300R for a 42′ offshore fishing catamaran. Which is the better engine for this application? Would I notice a difference between the AMS and HD midsections?

    1. Kevin,

      Most will opt for the V8 Verado on a quad application. The AMS offers less vibration, a switchable exhaust which keeps the engines quiet, and integrated hydro electric steering. The 300R is designed to offer slightly better top end speed with it’s additional performance parts and extra 200 RPM limit. Rigging the 300R would end up being more costly due to the steering needs as well.


  19. Hello,
    I have a 2006 Bullet 20XD that I upgraded from the 250XS to the new 300R back in October of last year. The 20XD has a 12″ manual rapid jack and I’m running the new fat sporty with 1.75. I started with Bravo XS 32p 1/2″ above pad and worked my way up with not luck. The issue I’m is getting the boat on plan, it will start and once bow starts to drop the motor will start spinning like you’re on a drag strip. With light load you can keep patting the gas and she’ll finally hook up but with heavy load it will never get on plan once it starts spinning. Any suggestions on engine height and prop selection is greatly appreciated.

    1. Ricky,

      Have you considered a hydraulic plate? I know a MAX5 prop would help but going with a hydraulic plate may be the best bang for your buck. The Bullet guys I’ve talked to so far plane off with the prop shaft measuring about an inch below the pad, then raise the jack plate up to around 1.5″ above pad on top end.


  20. I’ve got a bullet 21xd with a 2.5sport thinking about changing to a 250or a 300 4stroke probably the pro CSU motor more likely what size of prop would i need to shot for

    1. Jon,

      With the 300R on Bullets with a 1.75 ratio, most guys are running a 31 pitch MAX5 ST. With a 250R, most likely looking at a 29 pitch in the same prop.


  21. Looking to order a new 300R w/ tri-ram and Sportsmaster to replace my 260ROS w/1.87 SM small shaft. I’m currently seeing between 103 and 106 depending on load with a 27 SRX on my 21 RC Riot. I’ve spent thousands trying at least two dozen different prop designs/pitches but the SRX always worked best. I imagine the new SM is large shaft so I will require a new prop. What suggestions do have have in regards to prop and gear ratio?

    1. Charles,

      Sounds like an awesome setup. We recommend the 1.75 ratio for single engine applications. The size of the new Sport Master gear case requires it to be run higher than the 2.5L or 3.0L Sporties. Typical prop shaft height is 1.5 to 2 inches above bottom. Most guys are switching over the MAX5 ST to improve both mid range fuel economy and drastically reduce slip on top end.


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