Running a diesel-like engine on gasoline is something that researchers have tried in the past. Diesel engines are 40 to 45 percent efficient in using the energy in fuel to propel a vehicle, compared to roughly 30 percent efficiency for gasoline engines. But diesel engines are dirty. As the Delphi engineers say, “Diesel engines are challenged to meet future stringent NOx and PM emissions regulations at acceptable cost.”
Tested on a single-cylinder engine, Delphi's approach is called a gasoline-direct-injection compression ignition. Engine-operating strategies leverage advanced fuel injection and air intake and exhaust controls. The researchers wrote a technical paper on the subject, which was presented at SAE, an association of engineers and other experts in aerospace, automotive, and commercial vehicle industries. Delphi’s team, Mark Sellnau, James Sinnamon, Kevin Hoyer, and Harry Husted are the authors of the paper, “Gasoline Direct Injection Compression Ignition(GDCI) Diesel-like Efficiency with Low CO2 Emissions.” Their experiments were carried out on a Ricardo Hydra light-duty single-cylinder engine, which they said was considerably flexible, with parts that can be easily interchanged.