• Mercury Racing Should Work Their Magic With The 3.4-Liter V6

    A 200 Horsepower V6 R-Series Engine Would Be A Compelling Option for Smaller Performance and Bass Boats

    So much has happened in the realm of performance boating over the last 15 or so years, and the emergence of Mercury Racing’s R-series high-performance four-stroke outboards continue to define and shape the trajectory of not just the engines themselves, but the boats that are designed to use them.

    In 2004, Mercury Marine created a cataclysmic event in the marine industry with the introduction of the supercharged four-stroke Verado. I was at the Miami International Boat show for that, and I still recall the audible gasps from among the hundreds of people looking on with near-disbelief as then-president Patrick Mackie signaled for the veils to be lifted on what was the most revolutionary and technologically advanced production outboard ever created up to then. Everything else in the industry at that moment seemed insignificant in comparison, and the Verado represented Mercury Marine’s intent to cast off the safety net of established four-stroke engine designs and create their own path forward. It was very exciting to witness.

    Whether or not the Verado itself was a product I would be interested in purchasing was not a consideration to me; I was most excited to see Mercury Marine taking the gloves off in its battle for market leadership with new four-stroke engine designs that might have been deemed too risky or costly for its competition.

    The Verado was an incredible success, and Mercury Racing would produce the 400 ROS competition outboard and the 400R consumer performance variant that put to rest the fears that a four-stroke outboard could never achieve the levels of performance of the two-stroke engines they would be replacing. But Mercury Racing was just getting warmed up for what was to come.

    As revolutionary as the Verado platform was, there would be no earned vacation at Mercury Marine and Mercury Racing. The supercharged engine that clobbered the industry was just a first step into a future that would continue with an astonishing series of new engines that defied expectations. The four-stroke, high-performance outboard had achieved a reality that most performance-minded boaters had not seen coming for a very long time, if at all.

    In 2018 at Miami, Mercury introduced their new 3.4-liter V6 mainline outboard. This was not a Mercury Racing product, and it was not designed for high-performance applications, but that engine’s design was a prologue of what was to come.

    The 3.4 was immediately different, with its hard angled, faceted design eschewing the smooth, friendly wide curves of contemporary outboards. This 24-valve outboard was lightweight, very slim, and produced excellent power. Most importantly to consumers, these new engines were easier to own and service.

    Mercury Marine's performance variant of the 3.4-liter V6, the 175HP Pro XS, offers more performance-oriented components than the mainline 175, such as tuned exhaust, exclusive electronic tuning, and a slight weight reduction down to 475 pounds. While certainly a fantastic engine for bass boats and other smaller craft, it is not available with the venerable Sport Master gearcase.

    Render of a 20-inch 200R with traditional offshore exhaust

    The new R-series engines rewrote the popular expectations on what a four-stroke performance outboard could be, and in doing so Mercury Marine and Mercury Racing suddenly leaped into the next generation of high-technology, high-horsepower outboards that handily eradicated the notion that two-stroke outboard engine performance was in a class of its own.

    Mercury Racing’s 4.6-liter R-series engines have it all – supreme power, compact packaging, ease of ownership and relatively light weight, especially for a V8. When looking at a 500R, it is almost difficult to realize that beneath that slim cowl exists such a powerful engine. Naturally, my thoughts gravitate to other possibilities that such engineering agility could be directed to. The R-series engine technology could provide an engine configuration that would be a compelling option for lightweight performance boats under 24 feet. That would be a high-performance version of Mercury’s 3.4-liter V6.

    The V6, V8, V10 and V12 models are all part of the same basic engine platform, being engineered from the outset to accommodate the multiple displacements that are now present. They all share some rotating assembly parts commonality, such as pistons and connecting rods as well as smaller components. It is an extremely flexible design that had never existed to this degree in any industry, and Mercury Marine continues to demonstrate this with the wide variety of outboards available that are based on it.

    A 200-225-horsepower R-series V6 would slot in very nicely for high-performance bass boats such as the blisteringly quick Allison BasSport Pro and Bullet’s own bass rocket, the 21SST. To be sure, boats like these can take full advantage of the power of the V8 R-series engines, however there are also benefits to be realized with a lighter-weight engine that could still provide very impressive performance while being more cost-effective to purchase and own.

    While most boats today are designed to accommodate the increased weight inherent with typical four-stroke outboards as compared to previous-generation two-stroke models, there are almost always benefits to consider with reduced weight on the transom of lightweight boats. This becomes compounded by additional equipment installed in many bass boats, such as power poles, hydraulic jack-plates and extra batteries.

    I mentioned typical four-stroke outboards in the above examples; however, the Mercury Racing R-series engines are certainly not typical by any means, which makes the prospect of Mercury Racing working their voodoo magic on the 3.4-liter platform even more intriguing. Let me expand on that.

    Mercury Marine already offers a main-line 225-horsepower, naturally aspirated 3.4-liter four-stroke outboard, however, a Mercury Racing version would be a lot more than just a horsepower number. A
    smaller version of Racing’s R-Drive gearcase would open this engine up to a lot more high-performance applications, and even flats fishing boats would benefit from being able to run the engine much higher on the transom than with the standard gearcase. Additionally, incorporating a low-restriction intake and exhaust system based on the V8 R-series engines would increase torque and imbue the V6 with a nice growl like any proper high-performance outboard should have.

    All of the engines based on this platform are surprisingly streamlined, underscoring Mercury Marine and Mercury Racing's unmatched engineering agility. It's a tight fit in there, and the midsection is designed to accommodate a catalytic convertor, should the need arise in the future. That would present a difficult engineering challenge if short-shaft engines would be designed.

    But what about a supercharger?

    Mercury Racing has undoubtedly been expressing their mastery of supercharging an outboard since the Verado launched in 2004, and there could be merit in developing a very small supercharger that could have a minimal effect on weight, while also maintaining the slender cowl packaging of the standard V6. Indeed, the 450R has the same engine cowl dimensions as the 300R, thanks to much different intake runners and the relocation of various on-engine components. Why not add a supercharger to the 3.4-liter V6?

    A supercharged version of the V6 would be a very compelling prospect, likely producing over 250 horsepower, but there are two important things to consider with that idea. A 250-horspower V6 would be somewhat redundant with the existing 250R, and the question of whether there would be any appreciable weight savings with a supercharger added to the V6 as compared to the 250R makes this idea a moot point. Let’s have a look:

    The Mercury Racing 300R weighs 512 pounds dry, against the mainline Mercury 3.4-liter V6 200 which comes in at 475 pounds with its lightest model. Already, the weight difference is minimal, and it stands to reason that a supercharged 3.4L V6 could be even heavier than the 4.6L V8. Remember that an R-Series V6 would naturally be offered with a high-performance gearcase, which is heavier than the standard unit. Of course, this is just a rough estimate, however, the weight differential between the two is not enough to really matter in terms of practical performance.

    There’s more to consider than just engine weight. This is where I think a 3.4-liter engine could offer a few advantages over the naturally-aspirated V8 R-series engines. A Mercury Racing 200-225 R-Series V6 would be a very compelling solution for bass boaters that want a high-performance engine at a lower price and operating cost than the 250R. With the high cost of fuel these days, economy has become a very important factor to consider for people that run their boats often.

    Do I think that Mercury Racing could surprise us with an R-series V6? I think there is a possibility, and if they do, there is little doubt that they will once again break new ground on four-stroke outboard performance like all of their R-series engines have done before it. It's a great time to be a high-performance boater.
    Comments 12 Comments
    1. 22R's Avatar
      22R -
      same here
    1. aj06bolt12r's Avatar
      aj06bolt12r -
      Same on desktop
    1. Tcatrett's Avatar
      Tcatrett -
      Same here.
    1. Scream And Fly's Avatar
      Scream And Fly -
      It should be visible now.
    1. sonicss33's Avatar
      sonicss33 -
      Still not visible on my iPad.
    1. oldschoolltv's Avatar
      oldschoolltv -
      Still won’t work the anticipation is killing me.
    1. Scream And Fly's Avatar
      Scream And Fly -
      Which error message are you getting?
    1. Scream And Fly's Avatar
      Scream And Fly -
      Sorry about that. It should be good now.
    1. aj06bolt12r's Avatar
      aj06bolt12r -
      Its working now thank you... Well said.. One thing I would have added, when considering the 3.4 v6 for the under 24 foot performance boat crowd is a higher rev limiter. As I'm sure you well know, some of the v bottoms in this category don't necessarily have the reputation of driving well with 34 pitch props. Something around 7k RPM limiter to play with would be a huge selling point for this market, especially if they offer it with solid mounts and a sporty with a warranty.
    1. PanRonnie's Avatar
      PanRonnie -
      If they really set their minds to it a lot can be done with the 150 four cylinder
    1. mjf's Avatar
      mjf -
      I'm glad someone wrote an article like this. It seems that Mercury only introduces new products in the 35,000 dollar and higher range. They need to be poked a little and more people need to respond to this article. I believe when the 4.6 four stroke v8 came out the block was made out of a new light weight aluminum in a new plant which reduced the weight. Can anyone confirm if the block on the 3.4 v6 is make of the heavier aluminum. I believe it is and this lighter aluminum would reduce weight if were to be used on the 225R.
    1. Tcatrett's Avatar
      Tcatrett -
      I been following all this. I have a project I'm working on now. 150 pro xs on my XB2002. 1.62 3.0 sport master. Just a test.
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