Posselt, A., Mai, A., Leder, M., Salvio, R. et al., "Advanced PFI: The Economical, High-Performance Systems Approach," SAE Technical Paper 2015-36-0392, 2015, doi:10.4271/2015-36-0392.
With Advanced PFI, Bosch has demonstrated that gasoline port-fuel injection is becoming significantly more energy-efficient by means of innovative system development. Advanced PFI combines fuel pressure increase, twin injection, PFI scavenging, and open valve injection.The use of Advanced PFI makes it possible to reduce consumption by 12%, with a corresponding decrease in CO2 emissions. The higher compression in the part-load range alone accounts for 2% of the reduction. The remaining 10% come from downsizing with turbocharging and PFI scavenging.At the same time, Advanced PFI allows a reduction in hydrocarbons (HC) emissions. Thanks to more homogenous air-fuel mixture formation and reduced manifold wall fuel condensation, HC emissions fall by 20% in the test cycle.And Advanced PFI also permits an increase in specific engine power output, with PFI scavenging achieving significantly higher low-end torque.