Porsche filed a patent on a six-stroke ICE.
I'm not going to try to explain it but if it works this is going to be very cool.
I'm not going to try to explain it but if it works this is going to be very cool.
Six stroke ICE.
- Thread starter BMWTurboDzl
- Start date
My question after watching the video: How would they keep the oil control rings from leaving oil in the intake ports as the piston passes the intake ports on the downstroke? I would think that this issue would make emissions compliance difficult (?)
Low saps and OPF? Clearly there's a lot of development required.
dnewton3
Staff member
Seems interesting but overly complicated.
As said in the video, there are benefits but also costs of complexity, etc.
But, when IC engines are fighting to stay competitive and beat ever tightening emissions limits, every little bit helps.
As said in the video, there are benefits but also costs of complexity, etc.
But, when IC engines are fighting to stay competitive and beat ever tightening emissions limits, every little bit helps.
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takes power to make power too many moving parts there has to be power loss. just adopt an Atkinson or miller cycle engine.
So he takes a swag at 25% more power. Pure guess but ok. But he says air fuel mixture goes in via the scavenging ports--I suspect this would be DI and thus this should be just air coming in through those ports.
So this has an intake valve and the scavenging port... air going into the engine has two paths in. Not sure if that makes for the best breathing, but it matches conventional 4 valve engines. [Not sure if possible here, but wouldn't a uniflow have better breathing if it didn't have to push air up through the poppet valve? it's one thing to pull down, but I'd think the airflow isn't as clean the other way--but I've no experience in fluid flow.]
I'd be concerned about the power loss in that ring gear, and more importantly, what happens as that wears. What goes sideways as things age out?
That ring gear allows for variable compression and some timing changes on those scavenger ports? Interesting degree of freedom.
I have to wonder, for the complexity that the scavenging ports add (what sealing is required around the wrist pin?), if it'd be better off nixing that and using conventional intake/exhaust valves only. Play with the lobes required for the different strokes, or even use different lobes on each valve (but that might lose some breathing). Sometimes too many new variables cause insurmountable problems.
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Interesting engine. I guess we'll see what comes of it.
So this has an intake valve and the scavenging port... air going into the engine has two paths in. Not sure if that makes for the best breathing, but it matches conventional 4 valve engines. [Not sure if possible here, but wouldn't a uniflow have better breathing if it didn't have to push air up through the poppet valve? it's one thing to pull down, but I'd think the airflow isn't as clean the other way--but I've no experience in fluid flow.]
I'd be concerned about the power loss in that ring gear, and more importantly, what happens as that wears. What goes sideways as things age out?
That ring gear allows for variable compression and some timing changes on those scavenger ports? Interesting degree of freedom.
I have to wonder, for the complexity that the scavenging ports add (what sealing is required around the wrist pin?), if it'd be better off nixing that and using conventional intake/exhaust valves only. Play with the lobes required for the different strokes, or even use different lobes on each valve (but that might lose some breathing). Sometimes too many new variables cause insurmountable problems.
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Interesting engine. I guess we'll see what comes of it.
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I was going to say exactly the same thing! Be sure to combine with an Audi-esque timing chain that takes a route similar to a corn maze
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We went from 2 strokes to four strokes on some engine designs so it doesn't seem a stretch to improve on existing technology for power & efficiency improvements. One last squeeze before EV? I think so... but very interesting nonetheless. Good post!
What doesn't Porsche do well?
PDK complicates the transmission too much so Porsche should have never invented that either.
I was not specifically saying Porsche doesnt do anything well. I was referring to automakers in general.
Porsche is a great car. Much prettier than any VW though. They do look like a frog. There is that.
