One of several interesting little surprises to come out of this week’s GM product technology showcase was the upgraded 6.6-liter Duramax V8. Unfortunately, the 4.5-liter diesel developed for the light duty applications remains on the shelf for now, but the big diesel is getting a significant revamp in 2010. First up is a new fuel injection system that takes advantage of the latest common rail technology with piezo electric injectors. The system now runs at 2,000 BAR (29,000 psi) and can do up to six injection pulses per cycle. This allows for more precise, slower and cooler combustion.
The lower combustion temperature reduces NOx production and the multiple pulses help reduce noise significantly. The 6.6-liter still uses a single variable vane turbocharger mounted on top of the intake manifold. Downstream, the engine also meets the latest emissions standards thanks to a diesel particulate filter and a urea injection SCR system. Read our drive impressions – and the news about biodiesel – after the jump.
[Source: General Motors]
GM will have first factory-certified B20 diesels vehicles next spring originally appeared on Autoblog Green on Thu, 13 Aug 2009 09:01:00 EST. Please see our terms for use of feeds.