Have you seen? 2

[lugnuts67]

I had been contemplating the limiting factor for the modern internal combustion engine and came to the conclusion that it is the valve design. Then I started to sketch out a rotating barstock system with ports cut into it and looked around on the net for similar ideas.

Has anyone else looked at the Coates engine (

http://www.coatesengine.com)?

It looks quite promising but they are not producing for the public - especially my old Pontiac.

 

[patprimmer]

Unfortunately, Greg is pretty well correct.

I still think that knowledge flows from motor racing to road cars, just not in the form of invention, and only as a fairly intangible trickle.

I think Honda learnt some fuel efficiency tricks from the days of fuel quantity limited turbo engine F1 days.

I wish I could remember the details

Regards

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[globi5]

I wish it was still a 'Petri dish for experimentation' as it was 25+ years ago, but the rules unfortunately do not allow it anymore.
It is possible to combine business and a high grade of innovation, but they're obviously not willing to take the risk.
Also, for instance, some wind tunnels of F1 teams are running 24/6 or 24/7. So they're possibly experiminenting more than ever but just not on new concepts.

It's also interesting to see that 25+ years ago they had fewer people and didn't have all these sophisticated 3D CAD/CAM and rapid prototyping tools and still generated quite a variety of designs in short order.

 

[globi5]

Back to the topic: The larger the bore/stroke ratio the larger the valves for a given displacement and thus reducing flow restrictions. However, I still believe the reason for a big b/s ratio is mainly to reduce piston speed, but valve sizing might also play a minor role.