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[Mr Skrunts]

Standard engine, with 1 cylinder having 4 valves and a bigger combustion area to suit.

Extra cam only works the extra 2 valves.

Bigger centre cylinder balances out the 2 smaller ones as well.

[Kevin Wood]

Standard engine, with 1 cylinder having 4 valves and a bigger combustion area to suit.

Extra cam only works the extra 2 valves.

Bigger centre cylinder balances out the 2 smaller ones as well.

But look at how the cams are driven. The exhaust valve on the centre cylinder opens once per revolution.  :-?

Kevin

[albitz]

And the valves on number 1 &3 cylinders are both driven from the same cam,not 1 inlet and 1 exhuast valve  each. :-/

[Kevin Wood]

And the valves on number 1 &3 cylinders are both driven from the same cam,not 1 inlet and 1 exhuast valve  each. :-/

Yep, and that cam rotates at half crankshaft speed. Therefore, 1 and 3 are definitely 4 stroke cylinders. Looking at the lobes that drive their valves the valve timing looks pretty conventional too.

.. And the other pair of valves on cylinder 2 are driven by the "4 stroke" cam. The timing of those valves is the same as the adjacent exhaust valves on cylinders 1 & 3.  :-/

Can you see why I wanted to see the manifolds yet?

Kevin

[Lizzie_Zoom]

Hmm. I'd be interested to see the manifolds.

Looks like an idea from the age of steam re-hashed if I'm on the right lines...

Either that or the chap who did the valvegear had had one too many.

Kevin

That is exactly what I think Kevin.  Compounding.  Two high pressure cyclinders and one low.

[Brick Tamland]

Taking into account that the inlet cams are moving much faster, it looks like that all the valves on the center cylinder will all be open at the same time :-?

What ever it is it'll never be a replacement for a v8 so I dont like it 

[cem_devecioglu]

 :-? :-?

3 cylinder with 4 stroke me thinks..really interesting set up

[Mr Skrunts]

Now you are starting to question yourselves.

Both valves inlet and exhaust can be driven off the same camshft.

What is the rotational direction of the crank.

Which valves are the inlet valves?

Is this just an optical illussion psstake.

Is it indeed a petrol engine.



The mind boggles.    :-/

[Andy H]

My theory....
Big centre piston acts as an air pump, camshaft running at crank speed controls intake valves to big piston.

Outer two pistons take turns to be charged with air from the big centre piston.

.. And the other pair of valves on cylinder 2 are driven by the "4 stroke" cam. The timing of those valves is the same as the adjacent exhaust valves on cylinders 1 & 3.  Undecided

The reason why the these valves open together is so the air from the big piston can pass into the little one.

[Brick Tamland]

Is it one of these compressed air engines?  :-?

[Kevin Wood]

OK. My whole theory.

Two little pistons 1&3 work exactly like a conventional 4 stroke engine. Intake valves closest to the ends of the engine. Exhaust valves at the centre. Crank rotates clockwise viewed from the front pulley (cam belt tensioner arrangement proves that).

Exhaust valves from 1 and 3 feed into the large central cylinder so the exhaust manifold just connects the two pairs of valves at the centre rear of the head as we look at it.

Gases (still expanding) from the little cylinders exert pressure on the large piston thus recovering a bit more energy from the charge, increasing efficiency. Large piston exhausts through the pair of valves nearest to us, and driver from the front cam at crank speed (engine will exhaust once per crank rotation so the middle cylinder is effectively a 2 stroke).

No reason why it wouldn't scale up to a V8. Would be 12 cylinders by then though. 8-)

Kevin

[Marks DTM Calib]

OK. My whole theory.

Two little pistons 1&3 work exactly like a conventional 4 stroke engine. Intake valves closest to the ends of the engine. Exhaust valves at the centre. Crank rotates clockwise viewed from the front pulley (cam belt tensioner arrangement proves that).

Exhaust valves from 1 and 3 feed into the large central cylinder so the exhaust manifold just connects the two pairs of valves at the centre rear of the head as we look at it.

Gases (still expanding) from the little cylinders exert pressure on the large piston thus recovering a bit more energy from the charge, increasing efficiency. Large piston exhausts through the pair of valves nearest to us, and driver from the front cam at crank speed (engine will exhaust once per crank rotation so the middle cylinder is effectively a 2 stroke).

No reason why it wouldn't scale up to a V8. Would be 12 cylinders by then though. 8-)

Kevin

Correct, it is indeed a 5 stroke engine and is being developed by the legendary high performance engine maker, Ilmor

so, if we consider

http://www.omegaowners.com/forum/YaBB.pl?num=1222761905

We get all the benefits of opening the exhaust valve earlier and still get great economy as we can recover additional power using the thrid stroke!

And how may you ask can you get a 5 stroke engine, simples, there are only 5 truely active strokes

[Marks DTM Calib]

More info here:

http://www.ilmor.co.uk/concept_5-stroke_1.php

[Elite Pete]

OK. My whole theory.

Two little pistons 1&3 work exactly like a conventional 4 stroke engine. Intake valves closest to the ends of the engine. Exhaust valves at the centre. Crank rotates clockwise viewed from the front pulley (cam belt tensioner arrangement proves that).

Exhaust valves from 1 and 3 feed into the large central cylinder so the exhaust manifold just connects the two pairs of valves at the centre rear of the head as we look at it.

Gases (still expanding) from the little cylinders exert pressure on the large piston thus recovering a bit more energy from the charge, increasing efficiency. Large piston exhausts through the pair of valves nearest to us, and driver from the front cam at crank speed (engine will exhaust once per crank rotation so the middle cylinder is effectively a 2 stroke).

No reason why it wouldn't scale up to a V8. Would be 12 cylinders by then though. 8-)

Kevin

Correct, it is indeed a 5 stroke engine and is being developed by the legendary high performance engine maker, Ilmor

so, if we consider

http://www.omegaowners.com/forum/YaBB.pl?num=1222761905

We get all the benefits of opening the exhaust valve earlier and still get great economy as we can recover additional power using the thrid stroke!

And how may you ask can you get a 5 stroke engine, simples, there are only 5 truely active strokes

I'm the same as my wife will tell you

[Chris_H]

More info here:

http://www.ilmor.co.uk/concept_5-stroke_1.php

That's confused me.  I thought they had become Mercedes and were powering the Brawns, Maclarens etc.