Suzuki DF350A, the most powerful of the Japanese outboard engines, introduces many innovations, like the new block ant the counter-rotating propellers.
If you think it’s just a step up in terms of power, you’re wrong. The new Suzuki DF350A is a heap of innovations, and it is very clear in the prominent statement by Suzuki Motor Corporation’s Yasuharu Osawa, Executive Director, Global Marine & Power Products Operation, who emphasized the great amount of work the company has invested in this engine. Three years of development for an engine that responds to a market that got more and more into outboard engines.
Suzuki DF350A: counter-rotating props and a 4.4-liter V6
First novelty is the 4.390 cc block, with 55° V six-cylinder architecture, 24 valve, bore of 98mm and stroke of 97. The maximum output is 350 HP (257 Kw) from 5700 to 6300 rpm.
The total weight is reduced to 330 – 339 Kg, depending on the shaft length. A very high compression ratio of 12:1 has been made possible only siding it with double injectors for every cylinder, stronger pistons thanks to a thermal treatment, and an innovative fresh-air intake.
The latter, called Suzuki Louver System, is one of the innovations of Suzuki DF350A on which the Japanese engineers have placed the highest emphasis. A special configuration of the circuit allows to separate the air from the water and the humidity, providing the system with 10 degrees colder air. At this point the dual injectors come into play, granting an optimum chamber filling and therefore better combustion efficiency, with an estimated increase in power of 3%. As for the pistons reliability, the higher pressure is borne by a peculiar (and expensive) thermal treatment of the head.
Counter-rotating props for Suzuki DF350A
It’s not big news, were not for they usage on an outboard. The advantages are obvious: smaller propellers, greater thrust balance and therefore more directionality (even backwards) without the typical side bias of the single propeller. Then again, increased efficiency granted by six blades instead of three. All completed with a gearbox that has been maintained its compact dimensions and a good hydrodynamic profile for better performance.
Three years of development
to respond to customers’ request
for ever more powerful engines
Cherry on the cake, the new Suzuki DF350A adds on top the well-established and appreciated technical features of Japanese outboards, ranging from Lean Burn combustion to reduce fuel consumption to Suzuki Precision System electronic throttle levers, from the characteristic non-alignment between the crankshaft and the transmission shaft to reduce dimensions, to the two-stage speed reducer for a lower final ratio (2.29:1) and a higher torque.
Wanna know why Suzuki is also a lot of fun? Read what they organized for us…
