Propulsion test: inboard, sterndrive, jet
Posted on 11 November 2008
Written by Eric Sorenson
Our powerboat guru pays a visit to Hunt Yachts to test power options on its new 25-foot center console
I recently spent two days running four different Hunt 25 Center Consoles, all with different power. It was a great opportunity to see, feel and measure the effects that different drives and engines have on nearly identical hulls.
The four propulsion setups were a 300-hp Volvo D4 diesel with Duoprop sterndrive; an inboard with the same engine and a smooth-as-silk five-blade ZF propeller; another Volvo sterndrive with a 375-hp 8.1-liter gas engine; and a Yanmar 315 driving an Ultrajet waterjet.
I tested the four boats for several hours each over the two days, and to my mind the 25 is one of the most seakindly, best-mannered, smooth- and dry-running vessels I’ve encountered. And true to its Hunt pedigree, the hull is quite rough-water capable. Here’s the skinny on how these warped-vee hulls (more on that later) performed.
I ran all four at 30 knots into 2- to 3-footers on Rhode Island’s Narragansett Bay. They were smooth, comfortable and straight-tracking — and dry as a bone at 25 knots in a beam wind. I spend a lot of time on many different boats, and very few 25-footers can run at 30 knots so comfortably into these seas. They just sort of whoosh into the next wave — lots of vertical motion, as with any boat in these conditions, but none of the jarring or pounding you feel on the majority of boats of this size or, in fact, much larger.
A word on high-speed maneuvering: For our high-speed turn tests, we started off at 3,000 rpm making about 30 knots, then put the wheel hard over and kept it there for three or four 360-degree turns. (We timed a 720-degree turn, then divided by two to halve the stop-watch error.) Even during this hard high-speed turn, heel never exceeded around 20 degrees. It was just the right amount of heel for the turn rate, which means you feel the centrifugal force right down through your feet, rather than being thrown outboard or inboard. Volvo even has a buzzword for this balanced heel-versus-turn rate, a “true turn,” which when you think about it works as well as anything.
The Hunt hulls I’ve run, regardless of propulsion, all have this characteristic, and it makes for a safer, more enjoyable platform to ride on. Some other sterndrives (and outboards) have a tendency to heel excessively or even skid out in a hard turn, and that loss of dynamic stability is both disconcerting and potentially dangerous.
The Hunt boats have the proper hull shape, with just the right recipe of chine width and down-angle, bottom deadrise, keel radius (roundness in cross section) and vertical center of gravity to make it safe and secure — and a lot of fun to drive — in a high-speed maneuver.
Keep in mind when reading each sea trial report that the accompanying speed, time to turn, and acceleration numbers vary depending on who’s driving the boat and recording the data, boat displacement, sea state and hull bottom condition.
What separates Hunt hulls from almost all of the rest on the market today is that the deadrise continuously changes starting at the transom, which typically has 20 or 21 degrees of deadrise. Basically, the chines run uphill starting at the stern, so deadrise in the middle of the boat (Station 5) is more than it is on an ordinary monohedron deep-vee, even with its greater transom deadrise of about 24 degrees.
This means the 20- to 45-knot warped-vee Hunt bottom will have a smoother ride than the average monohedron, which carries its transom deadrise forward to the middle of the hull, making it flatter where most wave impact takes place. Also, the Hunt’s natural sweet spot on plane is in the region most people actually run their boats — 20 to 35 knots — while a conventional constant-deadrise deep-vee typically comes into its own at 40-plus knots.
If you’re looking for an 80- to 100-mph offshore racing monohull, get yourself a conventional deep-vee, since they spend a lot of time hopping from wave-top to wave-top and landing stern first. For the rest of us loafing along at 30 or 40 knots, the warped running surface is smoother, dryer and easier to get on plane. With its lower running angle, visibility over the bow is better, the ride is smoother in a head sea, and, thanks to its longer on-plane waterline, dynamic longitudinal stability is improved. This last point is one of the reasons the Hunt bottom can handle a variety of propulsion types successfully; it’s more tolerant of varying longitudinal centers of gravity (LCG) and propeller thrust lines.
But don’t take just my word for the smooth ride; sea trial a hull designed by C. Raymond Hunt Associates, the New Bedford, Mass., naval architecture firm named after its pioneering founder. But first a word of advice: don’t waste your time in calm water. Take it out when the wind is blowing hard. There are a number of manufacturers building hulls designed by Hunt Associates. All Grady-Whites have Hunt hulls. You can try a Grand Banks Eastbay, one of the bigger Four Winns, a Chris-Craft Roamer 40, Wellcraft 360 Coastal, Global 68, a Southport or any of the high-end Alden yachts. Or hitch a ride on any number of pilot boats or maybe a large custom yacht from Palmer Johnson. The important thing is to take one offshore and then buy the one with the layout you like best.
25 CC layout
Regardless of the drivetrain, the engine in the Hunt 25 Center Console is mounted in the center of the cockpit, forward of the transom, shifting the center of gravity forward when compared to transom-mounted power. It’s connected to the sterndrive or waterjet by a short jackshaft and, with in-line inboard power, directly to the propeller shaft. The cockpit deck lifts out, fastened around its perimeter with screws, and the deck flange mates to a gutter that drains and channels water quickly aft and out through the scuppers. This lets you replace the fuel tanks in a few hours — or the entire drivetrain, if necessary.
A transom seat lifts out if you need more fishing room, making the cockpit versatile and family friendly. The large center console has a compartment that sports a marine head, shower, sink and 72 inches of headroom.
The helm is ergonomically laid out, with the wheel and throttle comfortably positioned and angled at just the right height. The electronics flat is up high for easy viewing, and the engine gauges are down where they can still be seen, while allowing prominence of place for the GPS/plotter and radar. The boat is well-equipped for fishing, with a bait well, fishbox, and plenty of rod holders and rod racks.
Along with a choice of propulsion, Hunt lets you pick hull and deck colors (bring a paint chip from a local hardware store) and offers a variety of upholstery fabrics and teak options, including washboards aft and toerails forward. The overall result is a custom-looking boat without the custom pricing.
A little history
Ten years ago, C. Raymond Hunt Associates decided to dip its toe into the boatbuilding business. “We’d been designing them for years for other boatbuilders, the government and commercial users,” says John Deknatel, the firm’s president. “So we figured why not build a few of our own as well.”
Winn Willard, vice president of Hunt Associates, took the lead in establishing the boat company, bringing in Peter Van Lancker to run it while staying on as CEO. Van Lancker, hard-charging and multitalented, built boats for 30 years at such companies as Boston Whaler, Black Watch and Chris-Craft and, in fact, oversaw Chris-Craft’s resurrection and transformation before parent Outboard Marine Corp. went belly-up. Ray Hunt, C. Raymond’s grandson, heads up engineering, and it’s obvious the apple hasn’t fallen far from the tree. A deep understanding of how boats work is the creative force at the company, which is based in Middletown, R.I.
A boatbuilding startup is always a risky undertaking, but Hunt Yachts had a few aces in its back pocket. First was the name. Perhaps no one has done more to transform the boating world than the late C. Raymond Hunt. If you own a boat with a vee bottom, you can thank him for the great ride. (Not that all of today’s deep-vees deliver a great or even a good ride, but that’s another story.) The other, of course, was its hull design.
During my visit to Rhode Island, I got a look at how the Hunt 25 is built. A layer of mat wet out in vinylester resin is laid down over the gelcoat. This premium resin-saturated laminate prevents blistering and minimizes or eliminates the crazing and cracking sometimes seen in more brittle resins. Only knit reinforcements are used in the hull and decks (no woven roving), and the hull support structure is supported by fiberglass-encapsulated, foam-cored stringers for stiffness, strength and moderate weight.
The bottom is solid glass, while the structural bulkheads and vacuum-bagged hull sides are foam-cored to create stiff, lightweight panels. The transom is cored with a 2-inch high-density foam called Penske board, which resists compression from the lower unit mounting bolts used in sterndrive and waterjet applications.
The hull-to-deck joint is bonded with 3M’s 5200 death-grip adhesive and fastened with stainless screws. The builder uses so much 5200 that they lay down a 3-foot-wide strip of paper on the shop floor to catch the excess. This is good for the boat owner, as the fiberglass will shred before the adhesive lets go, and forget about leaks. The builder also uses blind-bolted hardware, including rail stanchions and cleats, to prevent leaks from these common drip sources. In my opinion, the construction is as good, or better, than most production boats on the market today, producing a reliable, durable boat.
The 25 CC was designed from the outset for running very well with sterndrive, inboard or waterjet power — a unique offering in today’s powerboat market. Hunt is able to specialize in this niche precisely because it has the expertise to pull it off.
The Hunt 25 is a good boat for people who like choices. You can choose your power. You can choose how the boat looks and is equipped. Other than high-end custom builders, few other manufacturers offer such a range of propulsion options and encourage you to put your personal signature everywhere on board.
“We found that right from the start 10 years ago, our customers were attracted by the Hunt ride and the ability to really individualize their boat,” says Van Lancker. “Many of our owners have owned a number of boats and know just what they’re looking for, while others tell us how they spend their time on the water and look to us for guidance. Either way, we get a lot of satisfaction out of working with our customers to help them personalize their boats. The right answer around here more often than not is, Sure, we can do that.”
The Hunt 25 CC starts at $123,500 with the Volvo 375-hp gas sterndrive. Both the inboard and sterndrive diesels are roughly $25,000 options, while the Yanmar/Ultrajet setup is an extra $55,330. In addition to a wide choice of power, options include a T-top, aft stern seat, windlass, teak trim, electric head, bow thruster and full electronics.
Eric Sorensen was the founding director of the J.D. Power and Associates marine practice and is the author of “Sorensen’s Guide to Powerboats: How to Evaluate Design, Construction and Performance.” A longtime licensed captain, he can be reached at
This article originally appeared in the August 2008 issue.