Technical Why Twinair never really worked

[AndyRKett]

The survey says no unfortunately. The whole point of tests is to give people a good example of what their car will do in the real world, the Twinair is clearly a fail in this regard.

Note from that picture that the car with the least discrepancy between real world and test figures, is the biggest engine of the bunch.

What’s also interesting is that the extra 20bhp difference between the 85hp and the 105hp twinair equated to less than 1mpg difference in fuel economy, which goes to show how much difference an optimised engine map can do despite the big increase in power.

 

[AGH1965]

The whole point of tests is to give people a good example of what their car will do in the real world

That is what unknowing people like to believe...

Looking in the survey, I see both the 1.2 and the TA105 reach 47.6 mpg in reality. The TA105 performs much better though. Therefore I would consider the 1.2 being the true fail here.

 

[AGH1965]

the car with the least discrepancy between real world and test figures, is the biggest engine of the bunch.

Who cares about the discrepancy? I don't. The test results are just numbers that determine taxes. Nothing more, nothing less.

 

[AndyRKett]

That is what unknowing people like to believe...

Looking in the survey, I see both the 1.2 and the TA105 reach 47.6 mpg in reality. The TA105 performs much better though. Therefore I would consider the 1.2 being the true fail here.

The 1.2 is an ancient engine design that has been well developed over several decades.

The TA is an ultra-small ultra complicated engine with turbo and lots of clever and modern highly engineered technology, so to reach the same MPG figures in the real world as an ancient design, is the real fail, not only that but when the TA goes wrong, it goes really really wrong £thousand repair bills. The worse that goes wrong with the 1.2 is a head gasket which appears very infrequent on newer models and any garage can fix it with very little effort.

The TA is supposed to be a super-duper modern engine and extra economic and with next to no emissions yet in truth is manages to be equal too, what it is supposed to replace.

Your opinion is that the TA performs much better, but that is only conjecture, whereas the figures above, come from real-world testing of both cars side by side scientifically on the road.

Who cares about the discrepancy? I don't. The test results are just numbers that determine taxes. Nothing more, nothing less.

So if you had bought the much more expensive and complex TA over the 1.2 on the basis that it would be cheaper to run with better fuel economy, only to find out it was only 'as good' as the 1.2 and cost considerably more to repair and service, then I don't think you'd be quite so delusive.

 

[alexGS]

Note from that picture that the car with the least discrepancy between real world and test figures, is the biggest engine of the bunch.

What’s also interesting is that the extra 20bhp difference between the 85hp and the 105hp twinair equated to less than 1mpg difference in fuel economy, which goes to show how much difference an optimised engine map can do despite the big increase in power.

And I think this is the underlying truth, really... the 1.4 gives the most consistent economy, but is not the most economical. Over all of our 500 Lounge driving, we’ve averaged 6.1L/100 - the claimed figure is 6.2L/100 - so we are happy. It seems to work well in our driving conditions.

I’m still certain that the comments about supercar efficiency can be summarised as ‘not efficient in typical driving conditions’, otherwise they’d be turning in good mpg and low emissions too.

-Alex

 

[puntofan01]

Did you actually watch the video? He is an actual engineer, I think he knows a little bit more about engines and efficiency than you do. Small engines with turbos was a terrible idea for efficiency and the results bear it out, people with 1.2s get better fuel economy than most twinair drivers.

Yes, I did watch the video. No, I'm not an engineer, but I do actually have a basic understanding of how cars work, and how things can affect mpg.

Yes, utilising a tiny engine fitted with a turbo isn't especially economical, as I said, but the understanding I have is that replacing a N/A 1.6 with a lightly turboed 1.4 (for example,) would give a small improvement in real world driving.

 

[AGH1965]

whereas the figures above, come from real-world testing of both cars side by side scientifically on the road.

This relates to a question I have. Where do these "real mpg figures" come from? Besides, what is side by side testing on the road? On what road is that possible? Only motorways?

So if you had bought the much more expensive and complex TA over the 1.2

There was a time that FIAT stopped selling the 1.2 in my country, because at that time it was due to CO2 related taxes more expensive than a TA and therefore unsellable. So what is more expensive? More expensive for FIAT to make is not the same as more expensive for the customer.

cost considerably more to repair and service

Do you suggest that every TA breaks down? Is TA maintenance really more expensive? Why? Two spark plugs less...

 

[AndyRKett]

This relates to a question I have. Where do these "real mpg figures" come from? Besides, what is side by side testing on the road? On what road is that possible? Only motorways?

There was a time that FIAT stopped selling the 1.2 in my country, because at that time it was due to CO2 related taxes more expensive than a TA and therefore unsellable. So what is more expensive? More expensive for FIAT to make is not the same as more expensive for the customer.

Do you suggest that every TA breaks down? Is TA maintenance really more expensive? Why? Two spark plugs less...

I get the feeling I could spend an hour typing a very detailed and in depth answer to the question of how real world data is collated, however I'm gonna guess from your answer's already, I would be seriously wasting my time and even if you did read it all, you would still not believe any of it to be true.
So If you are interested and want to know all about real-world MPG testing, This link should tell you all you need to know.

The solenoid valves on the TA will all eventually fail, They are £1100 a piece. Lots of cars now reaching 6 - 8 years old with this problem and costly enough to write a car off depending on the model and age.

There is nothing like this on the 1.2 to replace. no turbo (turbos always go wrong eventually) no complicated balance shaft or associated bearings on the 1.2, so despite 2 less cylinders there are not less moving parts and the parts that are there are infinitely more complex and costly.

And due to the complexity of the engine, it is and always has been more expensive than the 1.2, the 1.2 not being available in your country temporarily doesn't change the cost of selling the cars, it just affects availability albeit only temporarily, now with real-world testing the CO2 figures are not dissimilar to the 1.2 and you'll see if you follow other threads on the forum, the twinair has been temporarily unavailable due to the new real world testing.

See this video from when the car was launched 8 years ago, not only did he find the same problems with the fuel economy and comment on the price difference and other pitfalls of the car, despite being otherwise positive about the new engine at the time .

 

[gazz_bee]

And due to the complexity of the engine, it is and always has been more expensive than the 1.2, the 1.2 not being available in your country temporarily doesn't change the cost of selling the cars, it just affects availability albeit only temporarily, now with real-world testing the CO2 figures are not dissimilar to the 1.2 and you'll see if you follow other threads on the forum, the twinair has been temporarily unavailable due to the new real world testing.

Has that been confirmed though? The other thread is mainly conjecture. The UK Fiat configurator doesn't currently have any TA options for the 500 but mainland Europe websites still do. (UK Fiat site also still shows the Panda with TA engine options).

 

[AndyRKett]

Has that been confirmed though? The other thread is mainly conjecture. The UK Fiat configurator doesn't currently have any TA options for the 500 but mainland Europe websites still do. (UK Fiat site also still shows the Panda with TA engine options).

I don't doubt you can still go and buy one, the dealer will sell you a group stock twin air unregistered or you can buy plenty of pre-reg cars.

The fact that it is not on the website currently ( and I am only talking about the 500) for any model of 500 or 500c suggests currently you cannot specifically order one to be built, but I am happy to listen to anyone who goes into a dealer at the moment and asks to order one.

Conjecture is opinion, It is not anyone's 'opinion' that the Twinair is not on the website, for the 500 at the current time.

 

[ahmett]

And I think this is the underlying truth, really... the 1.4 gives the most consistent economy, but is not the most economical. Over all of our 500 Lounge driving, we’ve averaged 6.1L/100 - the claimed figure is 6.2L/100 - so we are happy. It seems to work well in our driving conditions.

I’m still certain that the comments about supercar efficiency can be summarised as ‘not efficient in typical driving conditions’, otherwise they’d be turning in good mpg and low emissions too.

-Alex

I am on 7.4l/100 km usually = ) Best I've gotten is 6.8!

 

[ahmett]

I don't doubt you can still go and buy one, the dealer will sell you a group stock twin air unregistered or you can buy plenty of pre-reg cars.

The fact that it is not on the website currently ( and I am only talking about the 500) for any model of 500 or 500c suggests currently you cannot specifically order one to be built, but I am happy to listen to anyone who goes into a dealer at the moment and asks to order one.

Conjecture is opinion, It is not anyone's 'opinion' that the Twinair is not on the website, for the 500 at the current time.

So wait, you can only order the 1.2 Petrol or the 1.3 Diesel? Wow! I should keep my 1.4 forever then, it is an antique!
I am sure the engine will go on forever, it barely uses any oil after over 160,000 kms.

 

[AndyRKett]

So wait, you can only order the 1.2 Petrol or the 1.3 Diesel? Wow! I should keep my 1.4 forever then, it is an antique!

Nope, at the moment in the uk you can only buy the 1.2 69hp

No diesel option, no TA option and no 1.4, in fact you’ve not been able to buy the diesel for a while and the 1.4 for longer than that.

 

[ahmett]

Nope, at the moment in the uk you can only buy the 1.2 69hp

No diesel option, no TA option and no 1.4, in fact you’ve not been able to buy the diesel for a while and the 1.4 for longer than that.

That's insane. Is it affecting sales? I don't see that many Fiat 500's on the road anymore.

 

[AndyRKett]

That's insane. Is it affecting sales? I don't see that many Fiat 500's on the road anymore.

It still sells well in the uk, but now they have massively restricted the engine choices it remains to be seen how much that will affect sales.

 

[JCarp16]

Maybe they are going to start using the new engines (the ones they launched in the Renegade facelift). The last I heard is that Fiat's current future model plan was 500 and Panda. The Punto will not be replaced. The new guy at the helm, Manley, - a Jeep man, is unlikely to change that. He will want to go where the profits are.

 

[gazz_bee]

I don't doubt you can still go and buy one, the dealer will sell you a group stock twin air unregistered or you can buy plenty of pre-reg cars.

The fact that it is not on the website currently ( and I am only talking about the 500) for any model of 500 or 500c suggests currently you cannot specifically order one to be built, but I am happy to listen to anyone who goes into a dealer at the moment and asks to order one.

Conjecture is opinion, It is not anyone's 'opinion' that the Twinair is not on the website, for the 500 at the current time.

I repeat what I wrote earlier and is continued in comments below. I fully understand the difference between fact and opinion. The 500 twinair is not available on the UK Fiat website configurator but is on the equivalent mainland Europe websites, both of these are facts. The reason why it is not available on the UK website is conjecture.

 

[AGH1965]

Where do these "real mpg figures" come from?

Sorry for the confusion, but I meant the "real mpg figures" 306maxi posted here. These come from the honestjohn.co.uk website, which is hardly scientific. Everyone can upload his own "achiefments" and influence the verdict.

Your opinion is that the TA performs much better, but that is only conjecture

Again sorry for the confusion, but I meant that the TA is more powerful than the 1.2 and therefore performs much better. Overtaking with the TA isn't the suicide mission it is with the 1.2.

 

[AndyRKett]

The reason why it is not available on the UK website is conjecture.

Ok I see your point, but what ever the situation it’s not available.

 

[AndyRKett]

Sorry for the confusion, but I meant the "real mpg figures" 306maxi posted here. These come from the honestjohn.co.uk website, which is hardly scientific. Everyone can upload his own "achiefments" and influence the verdict.

If you follow the link I left you can do your own research, honest John might be a commercial website, that doesn’t mean the information is incorrect.

sorry for the confusion, but I meant that the TA is more powerful than the 1.2 and therefore performs much better. Overtaking with the TA isn't the suicide mission it is with the 1.2.

The 85hp twinair is hardly a sports car, the 105 might be a bit more competent at getting a move on but neither car is going to breeze past traffic without a lot of effort and a lot of noise.