FEV Engine Technology Inc. (FEV) recently unveiled a developmental gasoline/E85 turbocharged direct injection (GTDI) engine that also features variable compression ratio (VCR) at the 2007 SAE World Congress. According to a company press release, the engine is being developed in-house, in tandem with several other DI engine projects that FEV is working on with various automakers. The engine boasts power similar to a V8 engine while delivering the fuel economy of a V6 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 V8 power from a V6 engine, this concept also provides a roughly 20%–25% percent improvement in fuel consumption.
Operation of the engine with a sensor or other means to identify the alcohol content in the fuel stream enables an optimal control strategy for VCR operation. During E85 operation, the engine can be operated at significantly higher compression ratios, with dramatic improvements in either performance or fuel economy, depending how the advantage is employed in the control strategy.
“While it’s still a developmental tool, we believe that we can achieve diesel-like fuel efficiency with a gasoline engine,” said Last. “The GTDI/VCR engine is just one example of advanced technologies that FEV is developing together with its customers that could ultimately reduce our dependence on imported oil.”