After three years of R&D, engineering and behind-the-scenes testing, Mercury Racing has finally unveiled the next big step in its evolution of the high-performance outboard engine: the fabled 450R, which boasts a 4.6-liter V8 FourStroke powerhead boosted by an exclusive supercharger to produce 450 peak propshaft horsepower and 40 percent higher torque than the firm’s massively successful 400R.

In only a few short years, the 400R has become the go-to option for speed enthusiasts: At the recent Miami Boat Show, virtually every speedboat on display seemed to be powered with at least a pair of them. (One model, Cigarette’s 59’ Tirranna, had installed as many as half a dozen.)

Mercury Racing gathered industry leaders and members of the press at a private function in Nashville, TN, on Monday and Tuesday to show off the new 450R, with ten boats on the water that had been outfitted with the 450Rs:

• Nor-Tech 450 Sport

• MTI 340X Cat

• Yellowfin 36 Offshore

• Cigarette Tirranna 59

• Wright Performance 420 Cat

• Mystic 3800 Cat

• MTI V-42

• Midnight Express 43

• Formula 430 SSC

• Sea Ray SLX-R 350

The release of the long-rumored 450 comes “about a year late,” according to Mercury Racing General Manager Stuart Halley, who briefed Speedboat Magazine editors on the details of the much-anticipated event. “We wanted to make sure we had a solid, stable product before making derivatives of it,” Halley explains. “So we waited until the engine was in a good place, then we really started working on this one again with a great deal of effort. After working on it for about three years, we ultimately decided that it was something that needed to have its own unique stand-alone launch event. It’s a really special product that our great team has put together.”

That’s why Mercury Racing selected Nashville, TN, to uncover the wraps on the new engine: “I think it’s fitting for our kind of customers. It has kind of a nice vibe to it.”

Of the two Marine Technology Inc. (MTI) hulls equipped with the 450 engines, one is Mercury Racing’s privately owned 340X tester (which took two of the outboards), while the other, a quad-powered 42′ MTI-V, is a factory demo boat. Tim Gallagher, Sales and Marketing Manager of the Wentzville, MO-based builder, was at the Nashville event and couldn’t have been more pleased by the boats’ performance.

“The power and torque is incredible,” he said. “These engines make 100 pounds more torque than a 400R, so now, when you stick four of them on the back of a boat, you really feel the difference. The boat is faster, but what’s most impressive is the acceleration. It gets up to speed in nothing flat, and surprisingly, it makes the same fuel economy at cruise as the 400R. That’s extremely impressive. They’ve done a great job. The motors are just what’d you expect—smooth and quiet, and they’ve got a really cool selectable exhaust function to let it make a little bit more noise. That’s a direct response to customers who have resisted making the switch over to outboards—people who say it’s just not the same experience. Well, now Mercury’s got this selectable exhaust that make the engines sound a little more throaty and more of a muscle feel to them.”

Among the major characteristics of the 450R:

• It’s smaller than the 400R, offering an industry-leading power-to-weight ratio in a compact, efficient package. “People don’t like the big, intrusive engines,” Halley says. “This one is the same size as the 300R, but it’s the 450R. And it’s the same weight as the 400R.”

• It runs on 89-octane (95 RON) pump fuel. “So if you were on a 400R on 89 octane, it’s probably even more than 40% torque difference. This engine is truly amazing.”

• The 450R offers unprecedented acceleration and top-speed potential with rugged reliability and the latest technology. Multiple gearcase, control system, tie bar, and styling options are available to create the ultimate customized outboard performance package, ready to run wide open all day long.

• Like the 400R, it features a three-year standard warranty. “And you can get the additional five years of MPP (Mercury Product Protection) if people want to buy that, which is a great deal,” Halley says.

• It’s based on the same 4.6-liter V8 powerhead used for the normally aspirated Mercury Racing 300R outboard models. The proprietary 64-degree aluminum block is topped with aluminum cylinder heads with a Mercury Racing Quad Cam Four Valve (QC4) design and double overhead camshafts (DOHC).

• The valve train features a high-performance intake cam profile and race-spec Inconel exhaust valves. The camshafts are chain-driven and run in an oil bath so there is no timing belt to maintain.

Halley said the 450 will finally extinguish a long-smoldering customer desire for a faster engine. “There’s so much interest in these bigger horsepower engines, especially one as phenomenally lightweight as this one,” he says. “The performance enthusiasts are really hungry for this.”

The question remains: How long will it take before the 450R is as common a sight on a boat’s transom as the 400R currently is? “That’s a really good question,” Halley chuckles. “I don’t really have an idea. Maybe it’ll be another three to five years before the market has been completely saturated.” Then, pausing to reflect on the sheer ubiquitous quality that Mercury’s product has had on our industry, he adds: “I don’t know if it does to you what it does to me, but it puts a tear in my eye every time I see it.  I’ve been through a lot of stuff in my life, and seeing these engines on so many boats is one of the coolest things I could ever imagine.”

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