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Wait a minute. We've had cam-less engines for years. They're called two strokers. The slobbering jimmy was a diesel but it did have a cam. Now use that same basic piston port design with forced induction and the cam can go away. Now we add high pressure direct cylinder fuel injection. Now you have an engine that weighs 2/3 the weight,produces twice the torque with no valvetrain drag. Wonder why a design like that is not in production now?
Opposed piston?
The Achates engine I think was swallowed up by the military and is therefore unlikely to see commercial sales. Auto manufacturers in any case are moving from ICE to electrification so are unlikely to commit to developing new (to them) ICEs such as 2T and opposed piston 2T. They should have done this years ago as the warning from the 1960s was that 2T would have to be revisited when NOx emissions became problematic. 2T is inherently low in NOx due to internal EGR (less than perfect scavenging) and the same torque and power as a 4T can be attained at half the BMEP (courtesy of twice the amount of firing strokes).
That looks a lot like the system developed by Australian company Bishop. The story goes that (in recent times) it was to be used in Formula 1 - then just before its adoption by whatever team, it was banned by the FIA. Could just be a story, but definitely there was a lot of press for Bishop's version.Coates was prototyping spherical rotary valve heads on Ford short-blocks thirty-something years ago.
www.coatesengine.com/csrv-system.htm
CSRV System
The Coates Spherical Rotary Valve System is one of the most advanced engine technologies in the worldwww.coatesengine.com
The problem though, is that none of the direct injection systems are perfect. They all struggle to atomise the fuel in the allotted time available. This will be exacerbated with low-volatility bio-fuels (ICE's only chance of survival IMO). There's a book on the subject here >> https://www.researchgate.net/public..._Injection_and_Emission_in_Two-Stroke_Engines
Because of the immense prejudice against 2T and auto manufacturer's reluctance to deviate from 4T. There's an expression that goes: 'Give the 2T engine to the 4T guy and watch him **** it up''. Probably true. Understanding the 2T engine as an orifice engine for someone schooled only in wheeze, squeeze, please and wheeze is a stretch.
Was it not the other way around? Wankel IIRC had a prototype that had the engine 'block' spinning before settling on the final arrangement - which was his invention with pumps subsequently cribbed from it - no?
The heat loss due to the large (and moving) surface area of the combustion chamber intrudes on efficiency though.
Love boost - or are particularly adept at spooling up a turbine due to the absence of an exhaust valve in the path of the outgoing exhaust stream and very quick port opening?
