Cummins, Inc., next-generation QSB engines have been put on display for the first time for the North American agricultural markets. The new engine features increased displacement, rear gear drive, High-Pressure Common-Rail fuel system and other enhancements for superior performance, durability and reduced noise.

The engines not only meet the EPA Tier 3 emissions requirements, but are fully capable of moving forward to the future Tier 4 requirements.

Cummins QSB engines feature advanced electronics, new sculpted blocks, rear gear trains and High-Pressure Common-Rail fuel systems. The Tier 3 QSB will be available in both a four- and six-cylinder platform, with displacement increased from 3.9 to 4.5 liters and from 5.9 to 6.7 liters compared to the current Tier 2 QSB. The engines are rated from 110-275 hp (82-205 kW) and are specifically designed to meet the durability, reliability and power density requirements of applications such as tractors, sprayers and combines where high performance and reliability is essential every acre.

The 6.7-liter QSB, rated 135-275 hp (101-205 kW), began limited production in June 2005, a full six months ahead of the emissions regulations; while the 4.5-liter QSB, rated 110-170 hp (82-127 kW), will be in limited production in December 2005, a full year ahead of the regulations. The 4.5-liter QSB has been increased from 130 hp to 170 hp (97-127 kW) from the Tier 2 engine, while both versions feature an over 55 percent reduction in sound pressure.

"We've enhanced the QSB with some evolutionary durability and reliability updates which move the engines significantly ahead of the competition. Cummins in-cylinder emissions solution has enabled increased performance while meeting regulations without the use of complex turbocharger arrangements or external hardware such as exhaust gas recirculation," said Dave Crompton, Cummins vice president and general manager of Mid-Range Engine Business. "These upgrades ensure long-term platform stability for the OEM beyond 2011 with the addition of after-treatment. Cummins is focused on providing engine platforms, customer support and technology to the agricultural market that are second to none in the industry every time," he added.

Engine sociability is becoming important not only in North America, but in some areas of the world noise levels are being legislated. To meet these new and impending requirements, Cummins has incorporated many enhancements that significantly reduce the noise level of the engines by as much as 9dBA. The new QSB utilizes a rear gear train, an enclosed valve tappet cavity, and a sculpted block to reduce the noise level such that the Tier 3 engine is as quiet at full load as its predecessor was without load. This is a benefit not only for meeting global requirements, but also enhances the operator's experience and reduces the potential for fatigue and distraction due to high noise levels.

Commenting on the new engine range, Marco Rangel, director of Cummins Agricultural Engine Business said, "Out in the field, tractor operators will be surprised at just how quiet and refined these engines are - thanks to the rear gear drive and other premium features, the level of noise and vibration is dramatically reduced. But more importantly, by closely evaluating tractor duty cycles we were able to precisely shape torque characteristics to achieve the best performance and fuel efficiency across the rpm range.

For added driving power when going uphill with a heavy trailer or plowing through a heavy patch of soil, these engines will offer an effortless response to load demands and reduce the need for gear-changing."

The Tier 3 QSB engines feature a full authority electronic control, High-Pressure Common-Rail fuel system capable of generating up to 1600 bar injection pressures which translate to refined and rapid power delivery, reduced noise and improved cold start. With the new fuel system, maintaining peak injection pressure is no longer dependent on engine speed, load conditions or fueling capability. Injection pressure can be virtually constant at all speeds, realizing greater flexibility and precision in controlling both injection rates and timing.

Along with precise injection control, the full-authority engine electronics equip the engine with a highly useful "power bulge" capability. For a limited period, the engine switches to a higher torque value for dealing with exceptionally high engine loads - such as combine grain tank emptying or when the tractor hits very tough ploughing ground. In fact, across the whole rpm range these engines offer smooth, highly responsive performance with deep reserves of power on hand every time it's needed.

The High-Pressure Common-Rail fuel system is fully integrated with Cummins high-precision electronic management, driven by an upgraded CM850 ECM (Electronic Control Module) with a processing speed over twice as fast as the previous ECM. The QSB engine management system continually maintains an optimum balance between load demands, fuel efficiency and emissions control.

The CM850 ECM is designed for isolation from detrimental thermal and vibration loading for extreme reliability and durability.

OEM and operator interface with the engine management system is made easy using the latest QuickCheck III handheld data link providing instant diagnostics, fuel efficiency data and multiple engine reports. QSB engines can be integrated into the equipment with PowerMatchTM software, Cummins industry-leading, OEM-focused application technology.

PowerMatch allows the equipment manufacturer to calibrate the engine specifically to the application. Torque curves and ratings can be tuned to optimize performance based on the specific requirements and changing needs of the machine's mission. PowerMatch provides the OEM unparalleled flexibility in designing a machine optimized for executing the work it performs.

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