How a Variable Compression Ratio Car Engine Works

[E39M62B44]

Variable compression brings undeniable benefits to internal combustion engine, but this implementation is not that great. Added number of moving parts, more rotating mass, complex manufacturing, bigger overall engine mass, more friction compared to standard engine with the same cylinder count etc. Most great benefits are lost in this design. If they used for example electric/magnetic valves and would lift whole engine head a little, things would be a lot simpler.

[Dotchetter]

That little cog next to the rod seems vulnerable to wear.. Up and down over and over. As quick as the pistons will go, the quick acceleration and deceleration of that cog cant be good for it and it seems to be a vulnerable component.. It would have to be oil acting as bearings for them to last as well and putting oil pressure in an area that high in the engine would expose it to the crankshaft which would turn the oil in to whipped cream.

[carlsbad337]

Methinks this's the same otto engine except for a variable compression. The rest is the same and even worse... You can make even a smaller engine with that power when increasing intake pressure. This is a marketing scam. Thus it makes the engine heavier than normally and I dont believe this bullshit about it costing 60% less.

[warezvz]

@carlsbad337 yeah 60 % less in cost of material but they charge you 3 times more

[GTAstuntking]

Dont'have seen any yet,

[mynamesmitchel]

So expensive to produce i bet. I want to make a VCR sled, so i can turbo it, and run excessive boost. but how...

When would your engine need 18:1 unless it is running on diesel? And is it direct injection?

What sort of mechanical losses do you thing you have from adding the second set of oscillating parts in the crank? Is that why it advertises max power at 1500 rpms?

[warezvz]

@mynamesmitchel its not so much costly because they are putting it into midclas cars.

The friction loss isnt that much of a deal because its all seqencial movament that is happening so the friction is minimalized trough th oil. Also the higher compression a engine has the more precize can it burn fuel so a 18:1 car engine is really great for low fuel consumption and the 8:1 engie is great for power bad bad for fuel economy. So the put a variable engine to have the car on good fuel economy

[warezvz]

@warezvz and by pushing the trottle the car switchs to 8:1 and has the large amount of torq and power. So you can have a engine that is powerfull but still you can run it on low consumption when you dont push it

[mylexicon2]

@mynamesmitchel

High compression ratio is beneficial at partial throttle. Watch the vid at 1:40 When the driver is hard on the gas, the compression drops to avoid predetonation at high cylinder pressure. When the driver lets off the gas and cylinder pressure drops, the compression ratio is raised to increase cylinder pressure, thus, power and efficiency.

[dandooshnanoosh]

...pleasure overload... an engineer's wet dream come true!  Close your eyes and think of it. Oh, I hope this is real and proliferates--it looks mature...

[warezvz]

@dandooshnanoosh the engine is in production for the european market.

[eCicerone]

But this VCR engine is suffering from the same weakness as most VCR engines (SAAB for instance), as soon as the piston at TDC doesn't provide any quenching effect due to the lowered CR the great benefits of the turbulence provide by the quenching effect is gone, only a tiny millimetre is required to spoil the effect, and as it seems in your engine the piston might be lowered probably at least up to 5 mm at TDC, any thoughts on this?

[warezvz]

@eCicerone the idea of the engines electronic is that it constantly balances out with the other 3 pistons so if one of them isnt providing the performances needed other 3 are, all pistons can be separatly adapted so there is no problem, even the moment of the lag exists it wont affect the performance because its only for a 100th of a seccond and on only 1 piston. So there are no real problems and much more benefits from the geometry of the engine

[terence20001]

Real interesting vid .

[betozoe]

when?

[warezvz]

@betozoe the production started in late 2010 for europe

cars are gonna be out at fall 2011

[starhobo14]

Very cool sir!