VIDEO: GM's Paul Najt talks about HCCI engines
Last summer we had the chance to meet up with GM powertrain researcher Paul Najt and drive GM's prototype HCCI engines. Homegeneous charge compression ignition engines basically take some of the technical concepts behind diesel engines and combine it with a gasoline engine. The result is a new power system that achieves most of the benefit of diesel efficiency without the problems of soot and NOx emissions. As features like variable valve timing, direct fuel injection, cylinder pressure sensors and more powerful control systems have become available in engines, HCCI has become more practical. HCCI doesn't work well under all operating conditions, but engineers are learning how to blend HCCI and normal spark ignition operation seamlessly. The guys at Popular Mechanics had a chance to visit the GM research lab where the HCCI engines are being developed. There is a good interview with Najt and some explanation of how the engines work in a video on their site.
Gallery: General Motors HCCI cars
[Source: Popular Mechanics]
Reader Comments (Page 1 of 1)
A.Brien 5:07PM (4/29/2008)
This technology will be perfectly in place in the volt car where the engine can spin at a constant speed in hcci mode to recharge the batteries.
Reply
Joseph 9:58PM (4/29/2008)
HCCI kind of seems like the equivilant of lean burn. It can only work under certain conditions, but puts out great fuel-economy.
I don't know of any cars being produce today, in America, that use lean burn. It sounds like lean burn might have issues with meeting the higher emmision standards (the Honda Insight which used lean burn is "only" ULEV rated)
From the sounds of it, HCCI doesn't have any issues with emmisions. I hope so.
Reply
mike 9:17PM (4/29/2008)
Even Better, would be to restore the EV1 Files!
And actually build it without the dealer paperwork trap, with a real factory and a plug you can connect to a real wall socket. Affordable would be nice too.
Sure, a 2 seater isn't for everyone, just about 30-40% of the driving public, as a second commuter car, to free us from Arab Oil( And global warming ).
Reply
Luke 10:51PM (4/29/2008)
Wow, the article actually says that you're saving the planet on the first mile you drive. So, instead of buying an existing used car, having a new car made from scratch is now saving the planet. I hope those of you who can afford it buy a couple dozen so that we get that much closer to saving the planet. LOL!
In addition, "payback" is defined by the difference between a new hybrid and a new non-hybrid. I guess it's time for those of you who are bad at math to rush out and spend 25k so that you can save it. LOL!
Reply
Luke 10:55PM (4/29/2008)
Doh! Please ignore my comments above. Wrong article.
Reply