Not very Matra related, although I'm sure this is the kind of technology Matra *would* have been involved in, if they were still around.
The US based company Delphi have produced a prototype petrol engine which uses "diesel" techniques to ignite and manage the combustion, which allegedly promises 50% better efficiency and even a lower particle count, which might push off the current (side-?)track of "hybrid" cars, lugging batteries and all sorts of exotic materials around...
http://delphi.com/pdf/techpapers/2011-01-1386.pdfIt has been tried before, but Delphi seems to be the first to apply enough smart management to circumvent some of the drawbacks (noise, rev-range etc)
/Lennart
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