This past summer, my cousin spent 13 hours at anchor in the water off Panama City, Florida, in a center-console with no T-top. When a part-time guide’s single outboard gave out during a half-day red snapper trip, my cousin and two other anglers aboard ran out of beer waiting on a tow service. Thankfully they had plenty of sunscreen.
Therein lies the enduring argument for twin outboards, especially for the risk-averse. Even with increased dependability and the multitude of single-engine boats regularly returning safely from offshore trips, there remains a slim chance of being stranded without a backup. That risk increases for boaters who are less than diligent with maintenance, which I suspect may have been true in this the case.
Beyond the safety benefits of a redundant system, there are other considerations that might outweigh the slight risk of having to get a tow when making the decision between one versus two outboards. The versatility and offshore capabilities of monohulls in the 23- to 26-foot range has made them some of the most popular saltwater fishing vessels on the market, which means there are a lot of boating anglers who must make a choice.
“This is a boat category for which many buyers need to look at the pluses and minuses of a single outboard versus twin outboards,” says Dave Greenwood of Suzuki Marine. “Neither choice is a bad one, but there are considerations that can influence your decision one way or the other.”
Here are some factors to think about when trying to decide how to power or repower your boat.
Cost Comparison
Two outboards are going to cost more, potentially twice as much as a single. This includes the purchase price as well as the cost of rigging and labor during installation. On top of that, you’ll have to pay for the regularly scheduled maintenance of two outboards instead of one.
Hole Shot
Generally, twin outboards get up and out quicker. Acceleration varies widely due to a host of factors, but two are usually better than one when it comes to a quick hole shot. With equal horsepower, twins have more blade area to punch out of the hole, which drives better acceleration. Yes, weight and drag are both increased with twins, but the added punch generally outweighs those factors during acceleration.
Boatspeed
Theoretically a single outboard should be faster than twins, all things being equal. But that is not always the case. Performance bulletins usually give the top-speed nod to a single outboard when horsepower and hull weight are equal. This is explained by the increased weight of two outboards when compared with one, as well as the increased drag on two lower units.
However, this is not always the case. There are instances when—all things being equal—twins post higher top speeds than single outboards. This could be due to setup factors such as propping and engine height.
Also, boaters often increase their horsepower when they decide on a twin setup. There is added expense, but there isn’t much added weight when considering twin 150s versus twin 200s. When compared with a single 300, you get a 100 hp boost, which makes for a big top-speed advantage.
Fuel Efficiency
The single outboard comes out on top if you’re looking to save money at the pump. A single is lighter weight and produces less drag than twins, all things equal. This results in better fuel efficiency.
Again, this generality is subject to numerous variables, but side-by-side tests give a slight advantage to the single at cruising speeds, with the fuel efficiency of the single performing even better in comparison at lower speeds. Consider whether you’ll mostly be running from spot to spot or if you’ll be doing a lot of trolling at 6 knots or slower if fuel consumption is an important consideration to you.
Boathandling
There is a clear-cut advantage to twin outboards when maneuvering in tight spaces. If you’re a boater who docks at a busy marina or needs to jockey the boat around at a crowded launch ramp a lot, the ability to use opposing thrust to help steer is a benefit worth considering.
With practice, it’s not too difficult to make a twin-engine boat spin on an axis, turn sharply without swinging the stern, and crab-walk sideways up to the dock. When it comes to negotiating tight quarters with current and traffic, increased maneuverability is peace of mind.
Some twin-engine outboards and steering systems also allow for joystick control, which makes piloting the boat at slow speeds thought-free and easy. These same joystick systems can also provide advanced virtual anchoring when connected to GPS positioning, similar to the anchor function of a GPS-enabled trolling motor. That said, some single outboards offer a joystick option, but there is less functionality with a single versus twins.
At speed, the added weight of twin engines on the transom might negatively affect the balance and ride of the boat, but this is more of an issue when repowering a boat originally equipped with two-strokes and not designed for the somewhat heavier modern four-strokes. However, many four-strokes now weigh about the same as older two-stroke versions.
Ease of Use
There was a time when running two or more outboards added to the hassle of boating. Today, thanks to technological advancements, a twin-engine setup is as easy to operate as a single outboard.
Even synchronization of revolutions per minute and trim angles is easy thanks to advances in electronic engine controls. All twin engines come with twin throttle/shift levers, but new systems allow control of revolutions per minute and trim for both motors with just one lever and trim switch while underway. Some power-steering systems enable you to turn multiple outboards with a finger.
There is no one-size-fits-all in the twin-versus-single-engine debate. If you’re in the market for a new saltwater fishing boat in the mid-20-foot range or if it’s time for a repower, consider the types of fishing and boating you do, and make your decision accordingly.
