The launch of the all-new Suzuki DF350A signifies the start of something special. While it’s not the first 350 HP to hit the market, joining the likes of Mercury’s Verado and Yamaha’s 350A, the difference in bringing the outboard to market has allowed the company to develop something completely new. Back when this outboard was still a concept, the technical team just about threw the book away on how to make a motor and instead started from scratch. The blank canvas was there for the creators to work without confines, in order to develop and incorporate new technology, making the 350 HP not only Suzuki’s latest and largest outboard, but also the most advanced!
So, what’s all the hubbub about that has whipped the world’s boating fraternity into such a frenzy? Let’s take a look at the technology that’s in this engine and after this giant leap forward, we’ll get into the nuts and bolts of how it really performs…
The business end
Aside from a 350 HP emblem on the cowling, the most distinguishing feature of this Suzuki is the counter-rotating propellers. Simply put; more blade surface equates to more grip. The added benefit of contra-rotating props is that it negates the need to mix right to left spinning outboards on multi-motor installations. While avid boaters may already know the performance benefits of a dual prop, consider that two props which spin in different directions offer evenly distributed torque across two inline gears which are smaller in diameter than are necessary with a single prop. This helps keep the gear case as small and hydrodynamic as possible to reduce drag, increase efficiency and boost top speed.
Keeping your cool
As with any outboard, Suzuki’s 350 HP uses two methods of cooling; both of which have been overhauled to ensure the engine doesn’t move more than 10 degrees above ambient temperature. To do this, engineers repositioned the primary cooling water pickup to the front of the gearcase bullet, with secondary pickup on the underside, just forward of the skeg. This creates a higher pressure to push water through the system.
To increase the power output of the 4.4-litre block (up 0.4 litres from the existing Suzuki 300HP), the engineering team increased the compression ratio to 12:1 – the highest so far for an outboard. To prevent knock with such compression, the DF350A features an intake in the engine’s cowling that feeds air directly to the engine. This keeps the air as cool as possible (a key to preventing knock), while a series of small louvres eliminate spray and moisture which can be found around the engine area.
Additionally, two fuel injectors per cylinder simultaneously deliver a finely atomised charge of fuel. This promotes a more-efficient combustion, also cools the intake air more effectively than a single injector and further prevents knock.
Tried and trusted
Although the new DF350A was designed from scratch, Suzuki has made huge leaps and bounds in their history to know what systems work best, and have therefore carried over a few of the features from the 300HP, including Lean Burn to maximise fuel efficiency, electronic throttle and shift for smoother control, variable valve timing for optimal low- and midspeed power and efficiency, and a selfadjusting timing chain that requires no maintenance. All-in-all, the systems come together to provide and outboard which is super strong, but light on fuel.
A feature which sets Suzuki light years ahead with the new 350 HP motor is an app for your mobile phone. Giving you real-time diagnostics, it allows you to troubleshoot issues on the go – or at least relay any issues you may encounter to a technician, saving having to take your boat into the shop just to get a technician’s opinion. Currently the app is only available on iPhone but it will soon be coming to Android users.
Put through its paces
While any manufacturer can take a big block motor, slap a huge propeller onto the gearbox and set the throttle to ludicrous, I think Suzuki have been extremely clever in coming up with the application use for the DF350A. While it is more than fast, it doesn’t try to set world water speed records. Instead, their 4.4 litre V6 is about brute force and putting that power to use, making this motor, certainly in my opinion, a strong competitor for the inboard motor market – but with the ease and convenience of an easily accessible, lighter weight outboard.
For the official South African launch, Suzuki had fitted the DF350A’s to a Classic 230 – which is outrageous yet ideal if you ever need to get somewhere in a hurry; as well as the very first Sensation 26 Deck outboard which has never been an option prior to the introduction of this motor. I focused my attention on the Sensation; weighing in at approximately 2 000 kg (which is light for a boat of this size due to its vacuum infusion moulding), I’d be able to hone in on the power gains of this outboard.
Admittedly, while there is no engine comparison available for this model, I don’t need a piece of paper to tell me what power feels like – and that’s exactly what you get, a surge of force from the moment you put the throttle down!
From the get-go, you can really feel the dual props biting in to give excellent holeshot, gripping the water as you accelerate, no matter whether you’re going in a straight line or around tight corners. Achieving a modest top speed of 77.5 km/h at 5 850 rpm when fitted to the Sensation 26 Deck, the engine was showing that it was slurping at a rate of 105 litres per hour – although that’s at wide open tap, it’s actually pretty good compared to some of the competition. At a more conservative speed of 40 km/h doing 3 900 rpm, the Suzuki was idly sipping just 33 litres of fuel per hour – which I put down to the reduced drag and improved hydrodynamics, as well as the Lean Burn control which has proven to optimise fuel efficiency.
With the throttle set to maximum, the engine lets out a mighty growl which is sure to please the ears of sport boaters.
It may be worth noting that the smoothness in the engine’s gears might not be spot on 100%. Although it’s by no means bad, it’s not as refined as I’d like; and if that’s the trade-off one has to make, it wouldn’t concern me, given the wealth of other plus marks I award the Suzuki 350 HP.
Lastly, the cherry on the top of this winning combination goes to the Suzuki enine management gauge. This neat, all-in-one visual system monitors engine details, is easy to use and won’t detract from other instruments you have fitted to the helm.
The Suzuki 350 is available in XL (25-inchshaft) and XXL (30-inch-shaft) models, which weigh in from 330 kg. You can get the DF350A in two colours: pearl nebular black and cool white, although I personally do prefer the traditional colouring.
The dealers at the launch were all well-impressed with Suzuki’s new flagship model and can’t wait to start fitting them to the array of suitable boats. To see a DF350A for yourself, visit one of the 32 authorised and reliable Suzuki dealers across the country.