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The S40/V50 PZEV (partial zero emission vehicle) model year (MY) 2007 has an upgraded hardware configuration for improved PZEV capability balanced with the best possible customer attributes. The base engine is the Volvo naturally aspirated inline 5-cylinder that, together with new technology, achieves PZEV emission performance with maximum cost efficiency. The engine out emissions were reduced by a newly-developed injection synchronization strategy during engine crank. The reduced number of engine revolutions during crank result in less hydrocarbon (HC) emissions from the cylinder pumping effect prior to the first cylinder combustion. Thanks to the Volvo developed start strategy that during lean lambda operation generates an extreme temperature ramp in the front part of the catalyst in a very early phase after cold start, in combination with a new unique oxygen-sensor installation, catalyst control is started extremely early.

To give the customer an immediate impression of quality several of criteria must be fulfilled such as styling, paint finish and fitting of outer panels/closures. Therefore, higher demands on geometrical quality e.g. stability for both exterior and interior are needed. The structural part of the car body is the key element for success. Beside the visual impression, lack of noise and vibrations during driving can convince a potential buyer to become an actual customer. To achieve this, car manufacturers have to draw up an overall strategy in combination with proper working methods to be able to guarantee a stable geometrical output throughout the entire development process and during series production over the lifetime of the vehicle. On a simultaneous engineering basis, the OEM, the system/component- and the process suppliers (for the industrial system from press shop to final assembly) have to adopt a common measurement strategy.

To elucidate the processes controlling the auto-ignition timing and overall combustion duration in homogeneous charge compression ignition (HCCI) engines, the distribution of the auto-ignition sites, in both space and time, was studied. The auto-ignition locations were investigated using optical diagnosis of HCCI combustion, based on laser induced fluorescence (LIF) measurements of formaldehyde in an optical engine with fully variable valve actuation. This engine was operated in two different modes of HCCI. In the first, auto-ignition temperatures were reached by heating the inlet air, while in the second, residual mass from the previous combustion cycle was trapped using a negative valve overlap. The fuel was introduced directly into the combustion chamber in both approaches. To complement these experiments, 3-D numerical modeling of the gas exchange and compression stroke events was done for both HCCI-generating approaches.

This paper compares and discusses the impact of conventional and improved start strategies on the design of the exhaust aftertreatment system. It is recognised that hardware measures on the exhaust side will not be sufficient if Volvo's 5 and 6 cylinder engines are to fulfil SULEV emission levels, assuming passive three way systems only. A new start strategy, providing an excessive heat profile combined with low engine out hydrocarbon emissions, was therefore developed. Temperature profiles, raw emissions and mass flow obtained with the Lean Start Calibration will be shown for the 5 and 6 cylinder engines, both naturally aspirated as turbo. The remaining part of the paper presents a brief history of the exhaust aftertreatment design modifications for Volvo's 5 cylinder N/A engine fulfilling LEV, ULEV I, ULEV II and PZEV emission levels respectively. The impact of the new start strategy on the cold start performance will be shown.

In the continuous struggle to improve car body properties, and at the same time reduce the weight of the structure, new materials and body concepts are being evaluated. In competition with more self-evident lightweight materials such as aluminium and plastic composites, new and different grades of high-strength steels with various surface coatings are being introduced. From experience it is known that to be able to weld and join these steel grades under high-volume conditions, it is necessary to perform comprehensive testing to establish those assembly parameters which give a superior and reliable weld quality. To meet the demands of cost-effective low volume production, we can notice a tendency to move away from traditional uni-body concepts and into the direction of space-frame structures. These can preferably be manufactured out of high-strength steels by using production methods like roll-forming, hydro-forming and hot-forming.

The article describes a model-based control method for idle speed of spark-ignition (SI) engines. It is based on mid-ranging, a multivariable control strategy that is more commonly used in process control. The basic building blocks of the control structure are two PI controllers.

The new SULEV legislation for passenger cars with gasoline powered engines, which will be introduced with the California LEV II program in the year 2003, requires a further development of the exhaust aftertreatment system. Three fundamentally different system approaches, each with very high efficiency in reducing cold start hydrocarbons, will be discussed in this paper. Vehicle test results will be presented to illustrate the potential of the respective systems towards the SULEV requirements. Durability aspects are also considered since an increased durability of 120 000 and even 150 000 miles is imposed by the legislation.

In May 1998 Volvo launched its most exclusive car model so far, the Volvo S80, which is aimed to compete with upper luxury segment products. The car is produced in the new production facility in the Torslanda plant in Sweden. Among the more highlighted features were a transversely mounted in-line six cylinder engine with a specially designed gearbox, electronic multiplex technology with 18 computers in the network, and safety features like stability and traction control (STC), front seats with integrated antiwhiplash system (WHIPS) and inflatable curtain (IC) for improved side impact protection. To fulfill the product's high demands on safety, quality and environmental care, the design, materials selection and assembly of the car body with high precision had to be very carefully engineered. As in previous product-/process development a holistic and concurrent engineering approach was necessary.