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Technical Supremo, Platinum Member
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Still trying to work it out could be wrong but it seems more exhaust gasses put into a cylinder so makes the egr valve look clean on todays cars would be interesting to see the head off after 50000 miles covered
Ron
 

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Not really a new idea. The idea of using expelled gases to drive another component is widely used in steam and gas turbine engines. In fact most steanm turbine engine have three phases, First being high pressure, the second being mid-pressure and the third being low-pressure. Looks like they have attempted to make this principle work on a standard internal combustion piston engine. In some respects 5-stroke is a bit of a misnomer as there are two conventional four stroke cylinders which export their exhaust gases to a scavenger cylinder which utilises energy gained from the expulsion of gases expelled from the other two. The downside I can forsee is that when the turbo needs energy at times of demand the third cylinder will not receive any expelled gases so in effect the third cylinder will only produce energy during idle or possibly cruising. So in effect the third cylinder will only work part-time. Direct petrol fuel injection has been tried previously such as Renaults and Mitsubishis IDE engines and we all know hiow that attempt failed miserably. Unless direct petrol injection improves greatly I can forsee problems.

At least it is good to see someone is trying to improve engine efficiency.
 

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Interesting, doesn't say whether coil or compression ignition. Either way, the BIG cylinder won't have any ignition, It extracts the power from the expanding gases which the exhaust usually deals with.
Like a double expansion steam engine does.
Yes it is EGR but for POWER, but not coz the EU says it should consume it's own bad breath.:eek:
As it's petrol not Diseasel it'll be reasonably clean, so no need to decoke, any more than on a conventional engine.
 
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Super Moderator Technical Supremo Platinum Member
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5 strokes, Suck, Squeeze, Bang, Blow, Wheeze

Seems to make sense.... the expanding exhaust gases in the third cylinder will be adding power and as long as the turbo is sized to suit the lower exhaust speeds/energy from the third cylinder exhaust, will still be performing.

Be good to see some real world driving results but gotta say, 130BHP from a tiddly 3 pot seems enough to satisfy many.

Coupled with the weight saving, are we to see some stonking new hot hatches ?
 

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Technical Supremo, Platinum Member
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The last 3 posts explained it so much better than the video well done lads
Ron
 

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Back in the real world..... what does grammes/ kW equate to in MPG ???
 

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Technical Supremo, Platinum Member
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Ilmor did a bit in MotoGP with a fair few wacky and ingenuitive ideas. They're a clever bin he of guys to be honest.
 

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Tartan terrorist in a dress..
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Looks like the way forward if they can get it right ...driving a 3 cyl picanto taday and it sounds like its screaming its head of climbing hills about here ..okay about town but couldnt pull the skin of your custard
 

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Sexy at 71 super mod..
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Looks like the way forward if they can get it right ...driving a 3 cyl picanto taday and it sounds like its screaming its head of climbing hills about here ..okay about town but couldnt pull the skin of your custard
I have found driving a 3 pot means you need to use your gears more..its not as forgiving as my 4 cylinder 1.2 clio3 was..if you drop below 30mph in traffic the engine wont pull in 4th gear..over all you have to go back to those diving school days and learn to drive again..but over all I'm happy with my 3 pot now..:)
 

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Technical Supremo, Platinum Member
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Which just goes to show they knew what they were doing when they compounded steam engines, Cosworth are likely working on a triple expansion engine.
 

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Looks like the way forward if they can get it right ...driving a 3 cyl picanto taday and it sounds like its screaming its head of climbing hills about here ..okay about town but couldnt pull the skin of your custard
New trend for small engines, very like the case with my Piaggio maxi-scooter ~ 350cc single cylinder, spends most of its time between 5 - 6k rpm. And only because I don't much like revving over 6k very often ~ at around 30 - 40 mph, it's 'only' 4.5k :d

But, up to 70 - 80 mpg...
 
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