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Old 11-08-2017, 10:57 AM   #27 (permalink)
Ecky
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Quote:
Originally Posted by joemac View Post
It actually is exactly lean burn. The only reason they are doing a spark-assisted variant of HCCI is to allow leaner operation. It will be interesting to see what they have to do for NOx emissions control to meet the Tier 3 emissions standards in the U.S. - that is a real challenge for any lean strategy, whether it is some sort of gasoline HCCI concept or diesel.
How lean, exactly, I wonder? Honda's lean burn motors run well at 22.5-24.0:1.

Are they going to need exotic emission controls?
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