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If you need more, there is the PattAir that fits even to Ferraris. Think why.

Manousos
Think why it hasn't been introduced on any production car to date.....

The data I have for a Mito with a 135Bhp multiair engine is 7.4l/100km, which is 0.1l better than the Punto illustrated with 30 Bhp more power. Why is this then?

A Punto 105 Multiair kerb weight - 1075kg Yaris - 1010Kg. The Yaris is 6% lighter than the Punto so not exactly a fair comparison.

The reason why the Multiair engine is up for so many awards isn't for the single NA derivative but for the performance/efficiency capabilities of the two turbo charged variants. Find another engine with that kind of power at that capacity with those economy/emissions figures.

Is it just a coincindence the the Pattakon site and yourself are based in Greece?
 

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i spotted the performance figures further up and yours for the punto are wrong.

the 0-60 for the punto evo 105ma is 10.8 not 12.3;) so id expect a faster, bigger engined car to be less economical wouldnt you?
 

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Discussion Starter #23
Think why it hasn't been introduced on any production car to date.....

The data I have for a Mito with a 135Bhp multiair engine is 7.4l/100km, which is 0.1l better than the Punto illustrated with 30 Bhp more power. Why is this then?

A Punto 105 Multiair kerb weight - 1075kg Yaris - 1010Kg. The Yaris is 6% lighter than the Punto so not exactly a fair comparison.

The reason why the Multiair engine is up for so many awards isn't for the single NA derivative but for the performance/efficiency capabilities of the two turbo charged variants. Find another engine with that kind of power at that capacity with those economy/emissions figures.

Is it just a coincindence the the Pattakon site and yourself are based in Greece?
In the comparative tests (the same journalist drives one by one all cars and tries his best) the Punto is slower than the Yaris. Punto prevails only in the maximum speed.

In the specifications given by the manufacturer, the figures are as you write: Punto is 1 second faster than Yaris at 0-62 mph.

The weight difference (Punto / Yaris) is small to justify the extreme difference in urban cycle consumption (6.2 vs 7.5 lt / 100 Km, i.e 20% worse).

In case you still think the weight causes the difference,
the same weight (1088 Kp) and power (105 bhp) VW Polo TSi (0-100 Km/h at 9.7 sec, 124 gr CO2 / Km at combined cycle, 6.8 lt/100 Km urban cycle) shows, just like the Yaris, that the MultiAir is not doing well at partial loads / low revs.

Both, Yaris and Polo, are more or less conventional engines while Punto is the high tech.

The MultiAir turbo versions (Giulietta 170 bhp, Mito MultiAir 170 bhp and 135 bhp, Punto 135 bhp) more or less keep the emissions / fuel-consumption figures of the 105 bhp naturally aspirating MultiAir Punto, increasing by far the power output and the torque.
Today no other carmaker offers such a combination of power output, mileage and emissions (170 bhp peak power, 5.8 lt / 100 Km combined consumption, 134 gr CO2/Km combined cycle for the 1355 Kp heavy Giulietta).

Yet, the good can be better.

And it is not a coincidence that both, me and pattakon, are from Greece.

Manousos Pattakos
 
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Maybe its the multiair punto evo had less than 1k mileage so it had reduced performace, or generally wasnt run in properly.

Or its that the multiair is geared more towards performace than the yaris engine? (e.g torque higher up the rev range).

Its common knowledge that the advantages of the multiair 1.4 105 engine isnt as impressive as its turbo counterparts.
 

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Stop using 0-60 times as a comparison of engine performance, unless you also look at the drag coefficients and several other parameters involved in a 0-60 time...
 

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Discussion Starter #26
Maybe its the multiair punto evo had less than 1k mileage so it had reduced performace, or generally wasnt run in properly.
Or its that the multiair is geared more towards performace than the yaris engine? (e.g torque higher up the rev range).
Its common knowledge that the advantages of the multiair 1.4 105 engine isnt as impressive as its turbo counterparts.
The most reliable data we have today for the cars are the official consumprion and emissions. This is so because the procedure is strictly defined.
Then it is the power output, the torque curve and the BSFC tables, if available.
Then it is the acceleration data etc.

Yaris 1.33 and Polo 1.2 were mentioned not because they are better (or worse) cars than Mito or Punto, but because they make obvious the point where the MultiAir engines can improve a lot.

The MultiAir (Ingoing Air Control) minimizes the pumping loss; and there is no need for a throttle valve to control the load (because the intake valves make the throttling).

Yet the "Ingoing Air Control" (MultiAir) has some inbuilt disadvantages.

After the intake valve closing, and as the piston moves towards the BDC, the charge (air or mixture) inside the cylinder expands; the expansion causes the charge temperature to drop, increasing the heat absorption from the hotter walls. As a result, after the BDC the piston compresses a hotter charge and so restores less mechanical energy than the mechanical energy consumed to expand the charge.
The lighter the load, the bigger this "mechanical energy loss".
Think about it: the less torque the MultiAir engine provides (partial load) the more torque (or mechanical energy) is consumed by the underpressure inside the cylinder.
Literally speaking, this is not a Pumping Loss, but what counts is not the name but the fact that it is a loss of mechanical energy: pure mechanical energy (generated at previous cycles) from the crankshaft-flywheel is consumed inside the cylinder of the MultiAir with only result the increase of the charge temperature.
Besides, the early closing of the MultiAir intake valves, that leaves more time to the charge turbulence and swirl to fade before the combustion, slow down the combustion. In order to improve the turbulence and swirl (and so to accelerate the combustion) the MultiAir uses the “late intake valve opening” strategy, which consumes even more mechanical energy (take a look at the P-V animation above).

On the other hand, with the "Outgoing Air Control" cycle (PatAir and PattAir) it is avoided not only the underpressure in the intake manifold (as the throttle-less VVAs, like the Fiat MultiAir and the BMW valvetronic, do) but it is also avoided the underpressure into the cylinder. The engine operates in a way similar to the Toyota Prius engine (Atkinson Miller cycle).
The late intake valve closing keeps alive the turbulence and swirl during combustion, accelerating the combustion and improving the efficiency and the clean exhaust.

Manousos
 

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Why are we discussing a Toyota on this site? I would rather drive a Multi Air Mito or Fiat than be seen anywhere near a Toyota - even if it did 0-60 in 1 second and used no fuel with 0 emissions! I have a passion for Italian cars particularly Alfas, I don't especially care what other manufactures are doing.

I think the Multi Air solution is a unique solution but it is not yet suitable for a high revving application. FIAT have already stated this - but this is just the first generation and a few years from now things will be different they say.

If you really want to save fuel my advice would be scrap the Yaris and buy a 1974 Alfasud 1.1
 

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So Manousos, looking at your surname I can assume you are the inventor (or co-inventor) of the PatAir system? If so kudos for looking at a way of keeping the internal combustion engine going for a few more years. I wish you the best of luck in finding a manufacturer to implement it.

On the face of it a naturally aspirated multiair engine is merely competitive with the majority of engines of a similar displacement and power, and in some cases perform worse (albeit subjectively).

What I would be interested to see, is a comparison with a turbo charged multiair engine, e.g the VAG 1.4 TSI. The engine does seem to be better suited to this application over NA.

FPT haven't designed this engine to be their eco-friendly option, lower overall consumption and emissions compared to other similar powered cars is an added bonus. You won't find many people buying an Alfa for its green credentials.

I thought all this sounded familiar then I remembered this monstrous thread from 3 years ago:

Pattakon engine.....legitimate alternative or just another fly-by-night - Ultimatecarpage.com forums
 

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Why not compare the multiair 105 engine to the non-multiair 95 engine? surely that would be a more effective comparison, as that actually shows that the mpg/performance is up 10%-ish compare to the old ones.
After all it's a system that gives a positive performance for cost value.

In fairness, it is possible that the yaris engine is fundamentally more efficient than a non-MA alfa engine, but it's not like every car company will use the same engine just because they are the "best"
 

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Discussion Starter #31
So Manousos, looking at your surname I can assume you are the inventor (or co-inventor) of the PatAir system? If so kudos for looking at a way of keeping the internal combustion engine going for a few more years. I wish you the best of luck in finding a manufacturer to implement it.

. . .

I thought all this sounded familiar then I remembered this monstrous thread from 3 years ago:

Pattakon engine.....legitimate alternative or just another fly-by-night - Ultimatecarpage.com forums
Yet, you can read again every single post in that forum (two different threads, the above and the "pure Genius") to see, in the hind sight, who was right and who was wrong.

Manousos
 

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i couldnt be any less interested what other manufacturers are doing. the MA is an improvement over the old starjet engine, which is what they were aiming for. more power quicker, more mpg, same size, and less emissions. thats what they were going for, and it worked.

end of argument:thumbs:
 
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Yet, you can read again every single post in that forum (two different threads, the above and the "pure Genius") to see, in the hind sight, who was right and who was wrong.

Manousos
Agreed. So no need for you to spam this board with a topic that is not about Alfas. We can read those postings and draw our own conclusions.
 
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Can someone wake me up when this is over, or when someone else comes up with a revolutionary engine designed on an etch-a-sketch...

Sent from my HTC Legend using Tapatalk
 

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If I want low emissions, I'll get on my bicycle ;) The only emissions then will be heavy panting when climbing up hills.

Multiair's only a start. Who would've thought that everyday hatches would one day get (theoretically) infinitely variable valve control? Soon they'll get similar valve timing/duration control on the exhaust valve, scavenging to reduce turbo lag, tiny turbos on each cylinder, an 80 jigawatt generator that runs on trash...

Still, what a strange way for a new poster to introduce him or herself. Also seems like the Pattakon fella's been on a few boards trumpeting this Pat/PattAir stuff.
 

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Discussion Starter #38
If I want low emissions, I'll get on my bicycle ;) The only emissions then will be heavy panting when climbing up hills.

Multiair's only a start. Who would've thought that everyday hatches would one day get (theoretically) infinitely variable valve control? Soon they'll get similar valve timing/duration control on the exhaust valve, scavenging to reduce turbo lag, tiny turbos on each cylinder, an 80 jigawatt generator that runs on trash...

Still, what a strange way for a new poster to introduce him or herself. Also seems like the Pattakon fella's been on a few boards trumpeting this Pat/PattAir stuff.
OK.
You have the best cars in the world.
And your engines are so perfect, that any attempt to improve them is useless.


Seriously now.

To control the exhaust valves by the MultiAir is not easy because the hydraulic system has to undergo way heavier loads because of the high pressure inside the cylinder just before the exhaust valve opening (things get worse for turbo engines).

The PattAir opens the valves true mechanically. The hydraulic system gets into play only during the valve closing. I.e. it fits to the control of the exhaust valves, too.

It also fits to high revving because it does not smooth (slow down) the opening ramp of the intake valves (racing engines, motorcycle engines, supercars).

It also provides way easier cranking (cold starting and start-stop) as compared to the MultiAir because it acts as an efficient de-compressor.

And above all, the PattAir avoids the underpressure of the MultiAir (and the relative energy loss) inside the cylinder, and improves the combustion.

Stupid things.
Details.
Who cares?
Yet somebody technically oriented (from FPT, for instance) may read them and respond.

Thanks
Manousos
 

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If I want low emissions, I'll get on my bicycle ;) The only emissions then will be heavy panting when climbing up hills.
Yes that's true but I have devised a different way of actuating the pedals, this means that you can actually increase the 360 degree pedal cycle to 720 degrees, thus increasing power and performance, whilst maintaining low emissions.

If i was that worried about emissions and fuel consumption I wouldnt buy an Alfa I would buy some eco friendly sandal wearing hippy mobile - but as it is I don't care I just want more cc and more POWER!

I will admit Alfa engines can be improved - they need to either reintroduce the Busso V6 or something equally as good!
 

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So go talk to the FPT folks directly, then.

Most of us here are enthusiasts about Alfas since that's what we own. They're not perfect cars either - most of the posts here are about problems and how to solve them. I couldn't care less if my engine had MultiAir or PatAir or whatever (which it doesn't), I'm not a mechanical or auto engineering graduate so most of what you're talking about goes over my head anyway. I just want to stop my driver's seat from creaking ;)

Did anyone here buy a Mito just because of the Multiair cylinder head? Do people buy BMW's just for Valvetronic?

Why don't you build a working prototype and show it to FPT/Chrysler/BMW/Toyota/Honda and see if they'll bite? Plenty of interesting engineering ideas get drawn up on CAD but never make it into mass production.
 
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