After Gutenberg

Firebird.com image from the NAPA Auto Parts Halloween Classic XII
An ethanol burning dragster… Since the 1960s mechanics have used high octane fuels to enable sophisticated, high performance tuning of drag race engines.

Green Car Congress relays a story from Director John Heywood and his colleagues at MIT’s Sloan Automotive Laboratory, who anticipate that direct ethanol injection could enable more highly turbocharged engines, consequently increasing their efficiency. The same power thus could come from smaller, substantially more efficient, turbo diesel engines.

Turbocharged boosting of an engine can contribute to engine efficiency, and thereby support the use of a smaller engine. The application of turbocharging, however, is limited by the occurrence of knock* under higher cylinder pressures.

* Note: Knock refers to auto ignition of unburned gas in a cylinder.

Injecting ethanol increases fuel octane and reduces temperature, thus reducing knock, which then allows “for more than a factor of two increase in manifold pressure relative to conventional, while also supporting an increase in compression ratio.”

The Car Boys note that direct injection of ethanol in a turbocharged gasoline-fueled engine would boost the overall fuel octane rating to more than 130. The high octane rating allows the engine to use massive levels of turbo boost without the need for lowering the engine’s compression to reduce knock. The Ethanol Boosting Systems solution uses small quantities of ethanol. The MIT researchers expect that a two- to six-gallon, auxiliary, ethanol tank would last for two to four months of driving.

There also was conjecture that hybrid cars could use such highly turbocharged engines in generators sets that provide electricity to the electric drives. Beside the use of more efficient, electric drives, HEVs (Hybrid Electric Vehicles) can increase efficiency by keeping the engine more often operating in an optimal range, whether gasoline, diesel or HCCI.