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I believe that all the Civic Hybrids have an OTTO cycle engine without any atkinson delayed intake valve closing behavior but has nice stuff like cylinder deactivation via valve closing. But I'm not sure. it seems like a mild hybrid type of setup so the engine still needs a good power band instead of being able to rely on the electric motor(s) for the power curve.

I heard that the 2013 Accord will have a hybrid version with an Atkinson cycle engine (http://www.treehugger.com/cars/2013-...rid-model.html).

I've also heard that some new Honda will have the 'Earth Dreams' engine; DI and Atkinson valve behavior.
http://www.digitaltrends.com/cars/wi...-than-a-dream/
It's kind of unclear if the regular Civics will get this engine in 2013.

But do the current Civic Hybrids have an Atkinson behavior? I don't think so but just checking.

Maybe after their first generation of 'Earth Dreams' engines, they'll have continually variable valve lift with electronics similar to 'valvematic'. Might boost MPG a tiny bit. Auto start/stop might come too.

Right now I believe Hondas engines just has continually timing and 2-stage lift but I'm not sure.

 
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believe that all the Civic Hybrids have an OTTO cycle engine

Yes, AFAIK.


Hybrids have an Atkinson

Many others use it already. http://en.wikipedia.org/wiki/Atkinson_cycle


but has nice stuff like cylinder deactivation via valve closing.

They call it "valve pause".

I heard that the 2013

I don't normally get much info until it really happens and shows up at the dealer.

No '13 m.y. anythings yet so far here.
Might boost MPG a tiny bit. Auto start/stop might come too.

Hondas hybrids already have auto stop.



I work in a dealer shop, so I'm usually among the last to know anything at all.
I heard automatic transmissions will be phased out in favor of CVTs starting in '13.
I have also heard rumors of bringing the European diesel versions over to the US if they can get the emissions down, but that rumor has been going for a few years now... Hasn't happened yet.

 
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I don't think Honda uses any sort of Atkinson-like cycle on their hybrids. Just i-VTEC and lean burn. Cars like the Prius use the atkinson intake valve behavior but no lean burn. Different approaches but the Prius achieves a bit higher MPG according to real-world results on fuelly.
Honda's hybrids will probably start having atkinson cycle intake valve behavior (at low engine loads) when they do their 'earth dreams' honda civic refresh, along with the regular Civics (besides Si)

It will be interesting to see if the Insight/Civic Hybrid/CRZ will have both atkinson cycle behavior at low loads AND lean burn mode, or have them separately or just Atkinson and regular OTTO when power demand is higher, eliminating the lean-burn mode feature. Or, just making it a full-time Atkinson cycle engine and upping the displacement due to the lack of HP/L with Atkinson cycle engines, like the Prius.

If they do it right they *might* challenge the Prius MPG.


Note: I don't think any cars on the road today are true Atkinson or true Miller cycle engines, they are just regular gas OTTO cycle where the intake valve(s) stay open part way up the compression stroke.

http://www.insightcentral.net/KB/com...ius-other.html
"Unlike most cars, including the Insight, the Prius uses the Atkinson cycle, where the exhaust valve doesn't close until after the upward stroke has begun. This effectively results in a higher expansion ration than compression ratio. The Atkinson cycle improves overall efficiency, though it does so at the cost of power."

 
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i think honda will be ruined if they make all the autos into cvts. i hope its only a rumor.

 
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The Atkinson cycle is designed to provide efficiency at the expense of power density, and is used in some modern hybrid electric applications. The Atkinson cycle, which is being showcased in numerous hybrid cars, is a style of motor that is set up for the utmost in fuel efficiency. Atkinson cycle engines complete all four strokes of the typical motor with one turn of the crank shaft, as opposed to two in an engine using the Otto cycle. The Otto cycle is four “strokes” of a piston inside a piston chamber: intake, compression, power, and exhaust. The Atkinson cycle explained, as it begins with the piston at the top of the piston chamber, or “top-dead center,” whereupon the piston descends, pulling in air and fuel. Then it returns to the top, compressing the mixture, where it is ignited by a spark plug and driven downward again. Then the piston returns to the top of the chamber, expelling the remaining gases and starting over at top-dead center.