The perfect engine?

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Wed 3 Oct 2018 14:49
The perfect engine? - badbusdriver

Reading October's issue of Car Magazine, i came upon an article about a UK company developing 'Intelligent Valve Actuation'. A bit beyond my level of mechanical understanding(!), but it does sound very interesting. Here is a link to the company in question for anyone interested,

www.camcon-automotive.com/all-things-iva/iva

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Wed 3 Oct 2018 14:55
The perfect engine? - Ethan Edwards

That will be banned. Nobody repeat nobody is going to allow a car to be a two stroke even for part of the time. Not with their emissions problem.

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Wed 3 Oct 2018 16:04
The perfect engine? - badbusdriver

That will be banned. Nobody repeat nobody is going to allow a car to be a two stroke even for part of the time. Not with their emissions problem.

I think you may have stopped reading prematurely, that is just one of an infinitely variable range of 'cycles' (?) it can do. This includes being a '12 stroke' during motorway cruising, which apparently involves each cylinder firing every third stroke. This is potentially cleaner than cylinder deactivation since there is no CO2 spikes as cylinders are reactivated.

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Wed 3 Oct 2018 16:36
The perfect engine? - oldroverboy.

mgf.ultimatemg.com/group2/engines/development_hist...m

Old hat I'm afraid... read at the very end...

Edited by oldroverboy. on 03/10/2018 at 16:37

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Wed 3 Oct 2018 16:52
The perfect engine? - badbusdriver

I suppose i shouldn't be surprised that this has been an idea for some time now. Perhaps though, it is only now that technology has progressed to a point where this might be made to work?.

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Wed 3 Oct 2018 22:25
The perfect engine? - Ethan Edwards

True but politicians and Eco Mentalists won't permit it imo

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Wed 3 Oct 2018 22:35
The perfect engine? - badbusdriver

True but politicians and Eco Mentalists won't permit it imo

As it has the potential to make the engine cleaner and more efficient, i'm curious to know why you think the folks most likely to view the technology favourably would not allow it?

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Wed 3 Oct 2018 23:09
The perfect engine? - SteveLee

This is probably a non-starter for the same reason the Rover lean burn design was killed off - the ecoloons demanded a can of toxic waste and heavy metals be bolted to your exhaust - which means carefully controlled exhaust gas temperatures, this did for ultra lean burn and compression-ignition petrols which pushed exhaust gas temperatures beyond what the cats can stand - the same problem exists if EGT is too low causing the cat to become contaminated rather than certain particles being burned off.

Still - who knows, perhaps the various funky cycles could still operate but within tighter parameters to keep the cat(s) happy *double banging" (two stroking) ,6 stroking and idling cylinders where appropriate.

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Wed 3 Oct 2018 23:44
The perfect engine? - Sofa Spud

It seems a bit like an update of the hit-and-miss engine of a century ago where output was regulated by varying the number of 'miss' cycles between power strokes.

www.youtube.com/watch?v=Om9gke04mQE

If the engine is to function as a 'valved' 2-stroke part of the time, then it would need a positive displacement supercharger to scavenge the cylinders, as on 2-stroke diesels. At least this would have a normal lubrication system, not a total-loss type as with the valveless transfer port petrol 2-stroke.

And if the engine switches from 4-stroke to 2-stroke at 3000 rpm, that 3000 rpm would suddenly sound more like 6000! I suppose it would just sound a bit like kickdown in an automatic.

Anyway it's all a bit irrelevant as the industry moves to electric cars.

Edited by Sofa Spud on 04/10/2018 at 00:02

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