The Bobcat engine is a new 5.0-liter V8 with gasoline port injection and turbocharging. A second set of direct injectors is used to feed a small amount of ethanol directly to the cylinders. The ethanol is used primarily for charge cooling allowing the engine to run at higher boost and compression levels. It also allows the engine to run much leaner. Normally, running lean causes higher combustion temperatures, increasing production of NOx. However, the ethanol helps to alleviate the NOx by reducing combustion temperatures. According to the data presented by Ford, they have been able to increase the brake mean effective pressure of a prototype E85 DI V6 engine from the standard 17 BAR to about 27 BAR.
BMEP is a measure of specific output of an engine that is independent of displacement. That BMEP of 27 BAR in a 3.5-liter V6 translates to a torque output of 553 lb-ft. Compare this to 350 lb-ft from a standard 3.5-liter Ecoboost. The 5.0-liter Bobcat can produce over 500 hp and 750 lb-ft of torque. That's the kind of torque number typically associated with big diesel engines and handily beats the 650 lb-ft of the 6.4-liter diesel currently offered in the Super Duty pickups.
The beauty of ethanol boosting in this way is that it can potentially offer better-than-diesel performance and efficiency without the expensive particulate filter and urea injection after treatment systems. If the concept can be scaled down effectively to smaller displacement engines, it could be the next step beyond the Ecoboost engines that are coming over the next couple of years.