Combination 2-stroke and 4-stroke engine

The 2/4SIGHT engine concept is based on an innovative combustion system combined with advanced valve train and control technologies, enabling automatic switching between two- and four- stroke operation. By matching the control strategy to make best use of the 2/4SIGHT engine’s capabilities, simulation studies have shown that the concept has the potential to deliver up to 30 per cent better fuel consumption and reduced CO2 emissions, compliance with Euro 4 and future emissions standards and attractive driving characteristics, with class leading torque delivery. A detailed 2.0 litre V6 gasoline engine design has now been completed which is intended to deliver levels of performance and driveability more usually associated with 3-4 litre V8. Ricardo and its partners intend to build and test the first concept demonstrator engine in mid 2006.

The 2/4SIGHT engine concept is viewed as being particularly attractive for premium cars and SUVs, where fuel consumption and CO2 emissions tend to be higher and its inherent torque benefits will fit well with typical driving characteristics. Work on the 2/4SIGHT engine is being actively progressed by Ricardo and a consortium of industry partners including DENSO, Ma 2T4, the University of Brighton and Brunel University, with additional support provided by a number of automotive manufacturers.

A detailed 2.0 litre V6 gasoline engine design has now been completed which is intended to deliver levels of performance and driveability more usually associated with 3-4 litre V8. Ricardo and its partners intend to build and test the first concept demonstrator engine in mid 2006.

In parallel with this work a detailed cost/benefit study is being carried out based on a 1.0 litre 2/4SIGHT engine for use in mid-sized family cars as a highly efficient replacement for a conventional 1.8-2.0 litre gasoline engine.

The 2/4SIGHT project

The 2/4SIGHT consortium includes Ricardo, DENSO, Ma 2T4, the University of Brighton and Brunel University, with the support of a number of automotive manufacturers. Following detailed system simulation which confirmed the potential for the engine, the project team has recently produced the detailed design of a proof of concept prototype engine which will be constructed and tested in mid 2006. This £1.9M stage of the project is part funded by the UK Department of Trade and Industry under its ‘Technology Programme’, with the partners contributing the balancing cost of the project. The targets of the research programme will be to validate the benefits predicted in the earlier simulation work through investigative testing of a research engine.

Ricardo’s role in the 2/4SIGHT is leadership and co-ordination of the project, design and development of the novel engine, and integration of its systems. DENSO is developing and supplying the gasoline direct fuel injection and advanced engine control systems. Ma 2T4 is contributing its knowledge of valve train switching technology. The University of Brighton will carry out investigative engine testing and combustion and cooling system analysis, and Brunel University will carry out transient engine testing and development. Work on this programme is expected to be completed in October 2007.