18 Dec 2013

DF175TG / DF150TG Lean Burn cutting edge Technologies

0 Comment

In Line Fours Offering the Ultimate In Advanced Features, Performance, and Fuel Economy

Advanced Technology for the Performance

*Data used in the graphs were obtained through “In-House Suzuki Testing” under uniformed conditions. Results will vary depending upon operating conditions (boat design, size, weight, weather, etc.)

Suzuki Precision Control (Electronic Throttle and Shift Systems)

Suzuki Precision Control is a technologically advanced computer-based control system that replaces the mechanical control cables found in conventional control systems with electronic wiring that eliminates the source of friction and resistance. While you enjoy smooth, little friction throttle and shift operation, the system’s computer is processing and transmitting commands in real-time to actuators at the engine that deliver precise throttle controls with smoother, decisive shifting. This is most evident in the low rpm range where operation is noticeably smooth and accurate. When combined with Suzuki’s Lean Burn Control System it allows control of fuel and air flow to boost the limit of the controllable revolution range improving fuel economy over a wide operating range. Suzuki Precision Control also features built-in systems that help guard the engine and drive against damage due to mishandling, and its design and simple wiring make installation easy, reducing the time required for rigging and adjustment.
The system offers precision control for single, twin, triple or quad installations as well as dual station operation.

Suzuki Lean Burn Control System

First introduced on our DF90A/80A/70A four-strokes, the Suzuki Lean Burn Control System is an intelligent fuel delivery system that achieves remarkable improvement in fuel consumption. The system predicts fuel needs through real-time monitoring of engine performance and operating conditions then delivers a leaner fuel mixture to the engine producing fuel saving benefits over the engine’s wide operating range, which includes the cruising range where the engine is used a majority of the time. In house testing shows that at medium cruising speeds, the DF175TG achieves a 16% improvement in fuel efficiency over its non-lean burn DF175.


Largest Displacement in Their Class 

Displacement plays is an important factor in the engine’s ability to produce exceptional acceleration and torque—generally speaking, the more the better. At 2,867 cm3, the title for largest displacement in the 129kW (175PS) four-cylinder four-stroke category goes to the DF175TG.

Big Block – High Performance Engine

The new DF175TG/150TG development team based both of these new Suzuki outboards on a big block inline four-cylinder four-stroke engine with a 2,867cm3 displacement. The block is topped with a DOHC powerhead that provides four-valves per cylinder for high performance. While the large displacement allows both to deliver exceptional acceleration and velocity, our engineers made sure that the outboard’s final dimensions are as compact and lightweight as possible.
Both outboards feature some of the best of Suzuki’s advanced technologies that have been developed to extend engine performance. The DF175TG incorporates the same variable valve timing system that is found on our flagship DF300AP and high-end DF250AP outboards to boost torque in the low to mid power range. Both outboards feature multi-stage induction and a 32-bit onboard computer that monitors and controls engine functions for greater performance, fuel economy and lower exhaust emissions.

VVT (Variable Valve Timing) (DF175TG)

Variable Valve Timing is utilized to expand the four-stroke engine’s power potential, creating an outboard that delivers high performance while retaining the benefits that four-stroke technology provides. Like the flagship DF300AP and DF250AP, the DF175TG’s 2.9-liter in-line four-cylinder engine incorporates an aggressive cam profile designed to deliver maximum output and performance from the engine at high rpm. Using Suzuki’s advanced Variable Valve Timing to vary the timing of the intake valves by optimizing camshafttiming, Suzuki engineers have gained greater low and mid range torque from the engine, optimizing power output across the entire operating range of the outboard. The system is controlled by hydraulic pressure from the oil pump and the process happens automatically so all you have to do is enjoy the power and performance.

*At the comparison test, Multi-Stage Induction System of the motor was operated.

Multi-Stage Induction (MSI)

Getting the right amount of air into the cylinder has a great impact on performance. High-speed operation typically requires a greater volume of air, low-speed less. Suzuki’s Multi-Stage Induction system meets these needs by utilizing two intake manifold pipes per cylinder to ensure the engine gets the right amount of air. At low rpm, air enters the combustion chamber through a longer, curved manifold pipe designed to improve combustion and boost low-end torque. As rpm increases, the valves open on the direct intake pipes. Shorter and lacking resistance, these pipes allow a greater volume of air into the chamber, increasing the engine’s ability to breathe efficiently at high rpm resulting in higher power output during high-speed operation.

Smooth Operation


The DF175TG/150TG incorporate large displacement, big block engines that produce a lot of power, but that doesn’t mean you have to give up on quiet operation. Quiet operation is an integral part of Suzuki outboard design, and a character that Suzuki four-strokes have long been noted for. Comparing noise levels between the four-stroke DF175TG and its two-stroke counterpart, the graph clearly shows that the DF175TG runs quieter than its two-stroke counterpart.

Counter Balancer System

One of the inherent characteristics common to in-line four cylinder engines when operating at high rpm is a secondary vibration that is directionally in line with the piston’s movements. To neutralize this vibration, Suzuki engineers utilize a secondary balancer system that counters the piston’s movement with a horizontal motion. To achieve this, the balancer is divided into left and right sections each rotating in an opposite direction at twice the speed of the crankshaft, effectively countering the secondary vibrations and producing smoother engine operation.

Thrust Mount System

Both outboards also incorporate a combination of two different rubber mount types designed to reduce engine vibration and provide stable operation. Both upper and lower mounts incorporate both soft type and high thrust rubber mounts. Soft type rubber mounts are designed to absorb vibrations generated in the idling through 2,000rpm operating range. High thrust rubber mounts provide stable operation under high loads while providing an improvement in power and performance.

Offset Drive Shaft

Pioneered by Suzuki, the use of the offset drive shaft on four-stroke outboards has long been utilized to reduce the size of the outboard. Found on all Suzuki four-strokes from the DF70A and up, this design positions the crankshaft in front of the drive shaft simultaneously moving the outboard’s center of gravity forward. While the design contributes greatly to the outboard’s overall compactness and improved power performance, it also moves the engine’s axis of inertia, the point where engine vibrations are at a minimum, up over the upper engine mount, thus greatly reducing vibration. These outboards also incorporate two-stage gear reduction designed to take maximum advantage of the power produced by these high performance engines. Providing a final drive ratio of 2.50:1—the largest you can find in either of these outboard classes—it delivers powerful torque for quick acceleration and great top-end speed.

Durability and Reliability

Suzuki’s Anti-Corrosion Finish

To guard against corrosion, Suzuki protects its outboards with its own specially formulated Suzuki Anti-Corrosion Finish. Applied directly to the outboard’s aluminum alloy, this finish provides maximum bonding of the finish to the aluminum surface. Layering an epoxy primer undercoat, black metallic finish, and clear acrylic fiber finish on top of this forms an effective treatment against corrosion, protecting those parts of the outboard’s aluminum alloy that are constantly exposed to saltwater.

Source: http://www.globalsuzuki.com/marine/tech175tg_150tg.html

About the Author