Quote:
Originally Posted by ChevyRules
But, it isn't a powertrain or transmission award. It's an engine award. The 6.0 was not really modified in any way to warrant the win. The LS3 deserves it more.
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The 6.0 in the Hybrids was motified to use the Atkinson combustion cycle, which is also used in the combustion engine in the Prius and a few other hybrids.
Otto cycle (normal gas and diesel engines): fuel and air are compressed the same amount they are expanded. If they're compressed 10 to 1, they expand 10 to 1 before exiting through the exhaust valve.
Atkinson cycle: it provides less power but more efficiency, because fuel and air are expanded more than they are compressed. They might be compressed 10 to 1 and expanded 12 to 1, which extracts more energy per unit of fuel.
That's why the 6.0 in the Tahoe and Yukon hybrid only makes 332 horsepower while every other current GM truck or SUV with the 6.0 gets at least 350 horsepower.