FEV Engine Technology is working on the development of a gasoline/E85 turbocharged direct injection (GTDI) engine that also features variable compression ratio (VCR).
The engine is being developed in-house, in tandem with several other direct injection engine projects that FEV is working on with various automakers.
The company claims that the engine boasts power similar to a V-8 engine while delivering the fuel economy of a V-6 engine, and avoids many of the traditional drawbacks associated with the use of alternative fuels that typically have lower energy densities.
‘This engine is a look at the future evolution of spark ignition engines as manufacturers seek to set a new standard for both power and fuel efficiency, yet face increasingly stiffer emissions requirements.’ said Robert Last, vice president of operations and communications for FEV.
‘And by mating the GTDI with variable compression ratio capability, it will allow customization of the engine control strategy to adjust for the use of alternative fuels such as E85 that tolerate combustion without knocking at a higher compression ratios.’
While offering the potential to generate V-8 power from a V-6 engine, the concept also provides a roughly 20 – 25 percent improvement in fuel consumption.
‘While it’s still in development, we believe that we can achieve diesel-like fuel efficiency with a gasoline engine,’ said Last.
The company’s VCR system features an eccentrically supported crankshaft that moves the TDC location of the piston by changing the crankshaft centerline position. Coupling elements are implemented between the crankshaft and flywheel/pulley to allow for the shift of the crankshaft centerline.
The packaging requirements and the mass of the coupling elements are similar to that of a standard dual-mass flywheel. The concept is also capable of being adapted to Integrated Starter Generators (ISG), which will become exceedingly important as more vehicles migrate to electrically-driven accessories such as water pumps, oil pumps and power steering pumps.