Honda unveils true Atkinson Cycle engine

Honda unveils true Atkinson Cycle engine
The host of modern hybrids to be found today are often partly powered by what their manufacturers call Atkinson Cycle engines. The truth is that none of them are true Atkinsons, primarily because the stroke of the engine is constant across all four cycles. Trick valve timing simulates Atkinson behaviour, but only to a point. True Atkinsons have shorter intake and compression strokes than power and exhaust. Honda has devised an ingenious solution, but as yet is only offering it on their small lawnmower engines.
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EL34EL34 - 7/27/2009 11:45:50 AM
-11 Boost
What is this engine supposed to do, land man on the Moon?

Welcome to 1969.

Wow, I'm impressed!!!!!!!!

WOW!


dumpstydumpsty - 7/27/2009 12:38:50 PM
-6 Boost
"Only Honda can do what everyone fails at."

...except building a true luxury car or SUV....


lexworldlexworld - 7/27/2009 12:18:39 AM
-9 Boost
"What! Who do you think you are fooling? Most of what Honda and Nissan does comes from their top rival The Toyota Motor Corp. Honda is peanuts compared to Toyota. No dis-respect but don't go there. I guess Tango you think if it's good enough for a Honda lawnmower it's good enough for a Honda car. You are what you are...but hopefully not a small thinker.


lexworldlexworld - 7/27/2009 12:20:39 AM
-2 Boost
And Badgewhore what are you talking about, Honda lawnmowers or Honda cars?


BremboBrembo - 7/27/2009 11:36:37 AM
+6 Boost
You tell him. And don't forget Jet engines too.


tangotango - 7/27/2009 12:43:17 AM
+4 Boost
Well, Lexworld, my posting of this bit of information is in no way implying my support of anything at all. If you want my opinion, you can ask. In fact, my opinion on the matter is that it's a good idea. Doesn't matter what the application or who is pushing it. Anything that improves upon the paltry efficiency (circa 20%) of the internal combustion engine is good for business. Homgeneous charge compression ignition (HCCI), variable compression ratio (VCR), variable valve timing (VVT), Atkinson/Miller cycles, direct injection (DI), controlled combustion engines (CCE), you name it, I find them interesting. I'm neither supporting Honda nor bashing Toyota, so you're really barking up the wrong tree, my friend.


DoctorCDoctorC - 7/27/2009 2:44:46 AM
+3 Boost
I just love Honda's engineers


DoctorCDoctorC - 7/27/2009 9:44:27 AM
+1 Boost
"That is SUCH a Samantha thing to say..."


DoctorCDoctorC - 7/28/2009 2:17:58 AM
0 Boost
Hope you are Samantha Fox.
I really liked her when she was in her 20's


Driver8Driver8 - 7/27/2009 3:50:08 AM
+1 Boost
I wish they could put there technology back into sportscars and racing. No F1, No more S2000 or replacement, No NSX.


kpaxxkpaxx - 7/27/2009 8:32:45 AM
-8 Boost
SAAB has an similar engine which predates honda's setup!


XYZZXYZZ - 7/28/2009 7:55:34 AM
+4 Boost
honda is THE premier engine company on the planet. not just in volume, but in advanced technology.

their TEN YEAR OLD motorcycle engines outclassed current NEW bmw engines until only recently. and 20 yr old honda bikes are STILL FASTER than brand new harleys with twice the engine size and more.

then, there's the Honda Jet...


answeranswer - 7/27/2009 12:42:28 PM
+1 Boost
Didn't the Mazda Millenia have this?


achilesachiles - 7/27/2009 2:17:02 PM
+2 Boost
The millenia S engine was a miller cycle engine not an atkinson, similar but not the same.


tangotango - 7/28/2009 12:04:36 AM
+3 Boost
The Millenia also falls into the "simulated" category. A Miller cycle is basically an Atkinson cycle with a supercharger added to compensate for the lack of fuel charge that Akinsons inherently encounter. In the case of the simulated Atkinson cycle it's the valve timing that is used to bring about the above-explaned effect. During the compression stroke, the intake valve is left open until the piston is about half way or so up the travel. Prior to this point there is no significant compresson taking place, but the piston works against the fuel charge. So if you leave the valve open there is reduced restriction in piston movement. The problem is that while the vale is open the piston is pushing some of the charge back out. This is where the supercharger acts to force that charge back in. I think it's six of one and half dozen of the other when it comes to cost of production and fuel savings. It burns about 13% or so less fuel than a comparable (power-wise) Otto cycle engine, but the costs involved are greater. If the Mazda engine was a true Miller it would have a crankshaft arrangement like the Honda above. The result is the same I suppose, but if variable valve timing is added to the engine above, coupled with variable compression ratio, direct injection, and (okay, lets put Ford in the argument) laser ignition, we might be on to something!


notme1212notme1212 - 4/18/2011 7:42:13 AM
+2 Boost
Fail troll.

Toyota has always been behind Honda in technology.

VTEC


grampaBgrampaB - 5/1/2012 2:13:22 PM
+1 Boost
And then there was the ill fated Chrysler turbine... oh well....


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