• The Mercury Verado 400 will fill the gap between the Verado 350 and the Mercury Racing 400R.

  • The lightest outboard in the category weighs as little as 668 pounds.

  • Power steering and digital throttle and shift are standard; Joystick control is an option.

The new Mercury Verado 400 model is the most-powerful outboard in the Mercury “mainline” portfolio. The 400-horsepower Verado 400 will butt heads in the offshore market with the 425-horsepower Yamaha XTO and the 350-horsepower Suzuki DF350A, and represents a step up in top-end performance from the Mercury Verado 350 model.

While these mega-motors may have originally been intended to power offshore fishing boats, they have become a common sight on the transoms of pontoon boats and larger freshwater fishing boats. Of course, we’ve seen as many as six big outboards spread across the stern of the largest new luxury center consoles.

Mercury Verado 400

The Mercury Verado 400 fills a gap in the Mercury outboard line between the Verado 350 and the Mercury Racing 400R outboards.

The Verado 400 slots between the Verado 350 and the Mercury Racing 400R models, and mechanically these outboards are essentially identical, built on the foundation of the Verado 350 and Racing 400R, introduced in 2015 and featuring a new cool-air intake tract and a water-cooled supercharger to boost the output of the 2.6-liter inline-six cylinder powerhead. All feature the Advanced MidSection that isolates the powerhead from the boat for very smooth and quiet operation, and also enables optional joystick control for multi-engine installations. These outboards all are equipped with digital throttle and shift controls and electro-hydraulic power steering.

According to Tim Reid, Mercury vice president for product development and engineering, Mercury has made more than 400 incremental changes to this outboard platform since the Verado 350 and Racing 400R were introduced in 2015.

“We’ve improved exhaust valve seat material for commercial markets with poor fuels,” said Reid when asked to cite some examples. “An investment in new gear grinding equipment produced quieter gear mesh. A retainer nut that was painted is now anodized for increased corrosion resistance, and we now directionally shot peen the pinion gear for high-load commercial applications. Some changes have more impact than others, but each is the result of an on-going product improvement program at Mercury that never stops.”

These Verado models are the lightest outboards in this category by a long shot. With a 25-inch shaft, the Verado models weigh 683 pounds, compared to 727 pounds for the 4.4-liter V6 Suzuki DF350 and 952 pounds for the 5.6-liter V8 Yamaha XTO. That’s a weight advantage for Mercury that really stacks up on multi-engine boats.

The Mercury Verado 400 is equipped with the stout HD 5.44-inch diameter gearcase.

Mercury achieves an escalating horsepower rating from the same powerhead through the engine control module (ECM), raising the peak rpm with a corresponding adjustment to timing and fuel delivery calibration. The Verado 350 wide-open throttle (WOT) rpm range is 5800-6400; the Verado 400 bumps that up to 6200-6800, and the Racing 400R goes even further, to 6400-7000 rpm. Horsepower is simply torque x rpm, and with a supercharger in place peak torque is not going to fall off much as rpm increases; Mercury can keep increasing horsepower output by raising the rpm until durability becomes an issue. I suspect that in terms of bottom-end and mid-range power, these three outboards will deliver very similar performance.

The Racing 400R has also been designed to have more immediate, “snappy” throttle response than you’ll feel from the Verado 350/400 motors. This is achieved in the calibration of both the throttle and the electronic boost control valve; the supercharger builds boost more quickly. Racing 400R customers like this snappy throttle feel for performance boats, and there’s a practical payback in situations where the driver needs to get off and then back on the throttles quickly when running at high speed in rough water. The Racing 400R also has harder upper motor mounts for improved high-speed stability and is available with either the HD 5.44-inch gearcase or the crescent-shaped Sport Master gearcase for boats running surfacing props above 85 MPH. The Racing 400R can also be rigged with a tie-bar between multiple engines, not an option for the Verado 350/400. The Verado 350 and 400 models are equipped with the HD 5.44 gearcase.

Like the Verado 350, the Verado 400 is offered in classic Phantom Black and three shades of white—Pearl Fusion White, Cold Fusion White, and Warm Fusion White. Mercury dealers and boat builders determine actual pricing, but the Verado 400 will start at about $34,000 in black, about $4,000 more than the Verado 350. The Mercury Racing 400R starts at about $35,000.

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Written by: Charles Plueddeman
Charles Plueddeman is Boats.com's outboard, trailer, and PWC expert. He is a former editor at Boating Magazine and contributor to many national publications since 1986.