Technical Why Twinair never really worked

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Technical Why Twinair never really worked

Yes, you can't have both at the same time. Interestingly, my wife bought a 1.2 500C last week, so I can compare it with my Twinair engined hatch that I sold around 18 months ago after 6 years of ownership.
Early days yet with the 1.2, but the trip showed 55mpg on the 30 mile trip back from the selling garage. Subsequent local runs have brought that down to 44. These figures are similar to those the TA would have given, perhaps a bit better in the case of the 55mpg - I had to try hard to get more than 50 from the TA.
The other thing to consider is the performance. While the 1.2 is entirely adequate, the TA has loads more mid-range torque, making overtakes much safer. We went for a 1.2 because the choice of cars available was much wider. Would we swap it for a TA? In a heartbeat!
 
Yes, you can't have both at the same time. Interestingly, my wife bought a 1.2 500C last week, so I can compare it with my Twinair engined hatch that I sold around 18 months ago after 6 years of ownership.
Early days yet with the 1.2, but the trip showed 55mpg on the 30 mile trip back from the selling garage. Subsequent local runs have brought that down to 44. These figures are similar to those the TA would have given, perhaps a bit better in the case of the 55mpg - I had to try hard to get more than 50 from the TA.
The other thing to consider is the performance. While the 1.2 is entirely adequate, the TA has loads more mid-range torque, making overtakes much safer. We went for a 1.2 because the choice of cars available was much wider. Would we swap it for a TA? In a heartbeat!

The point of the video wasn’t caring the TA to a 1.2 though.

It was comparing a TA style engine to something different, to this.

[ame]https://youtu.be/nxVOyL4r7Qc[/ame]
 
Frankly the gearing is too short on the Ta - and the power delivery inconsistent. So you end up driving it like you've stolen it.
 
You're right Maxi, I was a bit off topic in comparing available 500 engines.
I don't know if Suzuki did anything clever with the 1.6 120bhp N/A engine that was in my wife's S-Cross which she has just sold. That could achieve, on a run, over 50mpg, virtually matching the NEDC average. Not bad for a Qashqai size SUV. Performance was ok too. Needless to say, Suzuki have now replaced this engine with a 1.0 turbo, which has slightly less power but more torque. The NEDC figures have improved, but I bet the real-world figures don't. We'll see if the new WLTP tests are more relevant.
I'm not sure if that new Mazda engine is available in the UK yet. A mate of mine bought a Mazda3 a few months ago, and that has a N/A 2 litre Skyactive petrol engine. Only about 120bhp, but I think it's designed for torque. He says it goes well and sips fuel. Don't have any figures from him, but the HJ Real mpg is about 44, not bad for a 2l.
 
Frankly the gearing is too short on the Ta - and the power delivery inconsistent. So you end up driving it like you've stolen it.


If I'd stolen it, I'd be driving it back with an apology and my condolences.
 
If I'd stolen it, I'd be driving it back with an apology and my condolences.

Oooh That's harsh! The problem I always had was pulling out turning right in a dip, so you needed to pull out sharpish but within seconds first gear was done. Its a shame it doesn't rev higher as that would have really helped the gearing those tiny piston should manage 7k
 
The only petrol engine I would achieve over 43 mpg in town driving was the Audi A1 1.4 TFSI that had that 2 cylinders on/off thing. I was really impressed by its economy. With the 1.2 I would get about 40 in town, with the TA about 39. 1.4 37.

For fuel economy, I have a diesel = ) At least then I can drive it the way I want and still get above 50 mpg
 
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The only petrol engine I would achieve over 43 mpg in town driving was the Audi A1 1.4 TFSI that had that 2 cylinders on/off thing. I was really impressed by its economy. With the 1.2 I would get about 40 in town, with the TA about 39. 1.4 37.

For fuel economy, I have a diesel = ) At least then I can drive it the way I want and still get above 50 mpg


Only 50mpg?
 

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Frankly the gearing is too short on the Ta - and the power delivery inconsistent. So you end up driving it like you've stolen it.

they do improve considerably with mileage but i know what you mean, mine is really flexible and refined now at 41K compared to even a year or two ago, it happily pootles around in high gears, mpg on current tank is showing 54 on the trip and that's with mixed urban driving (and warm weather!)
 
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I had mine upto 10k then same engine again in Mito tuned to 115 bhp. Best I managed was 65.7 on motorway. Around town though around 38mpg compared to an easy 35 in the abarth.

I guess the abarth can just manage my driving speed whilst under less stress.
 
Twin cylinder engines don't turbo easily which is why Honda claim they chose to turbo the CX500/650 (AKA ORBOT or The Gasping Maggot) because it was difficult :confused:
http://www.motorcyclespecs.co.za/model/Honda/honda_cx500tc_turbo.htm


but to be fair it was better than the 4 cylinder bikes from Suzuki and Yamaha,only Kawasaki really made it work.
http://www.motorcyclespecs.co.za/model/kawasaki/kawasaki_gpz750_turbo 83.htm


and the Japanese Kei cars show it can be done with 3 or 4 cylinders
https://www.carthrottle.com/post/top-5-spicy-kei-cars-youll-want-in-your-garage/
 
The idea of using a smaller turbo engine instead of a larger N/A 1 for better economy is a genuinely good 1. The trouble is that the manufacturers took it way too far, resulting in cars with engines that whilst capable enough of moving the car, were too overworked to give good economy. A prime example being a 1 litre, 3 cylinder turbo Mondeo. If the manufacturers had kept things sensible, then it would've been a good concept.
 
The idea of using a smaller turbo engine instead of a larger N/A 1 for better economy is a genuinely good 1. The trouble is that the manufacturers took it way too far, resulting in cars with engines that whilst capable enough of moving the car, were too overworked to give good economy. A prime example being a 1 litre, 3 cylinder turbo Mondeo. If the manufacturers had kept things sensible, then it would've been a good concept.

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.
 
The idea of using a smaller turbo engine instead of a larger N/A 1 for better economy is a genuinely good 1.

No it isn't. It's a good way of getting better performance out of a a small engine, and it's one way of getting decent emissions & mpg figures under the old and now discredited testing regime, but it's not good for real world economy. A carefully driven 1.2 will take you a lot further than a carefully driven TA on a tank of fuel.

Manufacturers have put their emphasis on designing for performance, not economy, because that's what most buyers want and it's what sells cars. The TA is a prime example of that; it gives impressive performance for its capacity, but an engine for the dedicated eco driver it most certainly isn't.
 
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.



Maybe it would have been better to have small engines turbos, if they didn’t cater to the lowest common denominator. As they have to make a car they will survive any manor of mechanical mistreatment.

If they were able to make an engine that had a higher tolerances and better tuning it would likely be far better in terms of economy, however would be far more highly strung and therefore likely to break down if mistreated.

It’s this very reason that supercars tend to get far better economy figures for their relative engine size than small mass market engines. A supercar is far less tolerant of a bad driver but far more effective and efficient in the way it creates power.

So the twinair actually has the potential to be a good and very efficient engine, it is those who drive them who are the problem not saying anyone on here is the problem, but 90 year old Dorris who rides he clutch and drives everywhere in 2nd gear at 20mph and alike who have to expect a certain level of performance and robustness, that means fiat have to release a car to the mass market that isn’t as good as it could be. So as highlighted in the video, they have to put things in to work around problems caused by the turbo and small engine size (such as deliberate over fueling) where as with a high (more expensive) level of refinement the engine wouldn’t need these work arounds.

But then who would pay £30,000 for a 900cc two cylinder 100hp tiny hatch back ?

I suspect the reason for the Ferrari and Maserati as well as the biposto editions of the 500 with the 1.4 multiair with much higher levels of power, help fiat refine and research better tuning set ups on their usually detuned engines. They are more highly strung cars and only bought by certain types of people not the general public.
 
No it isn't. It's a good way of getting better performance out of a a small engine, and it's one way of getting decent emissions & mpg figures under the old and now discredited testing regime, but it's not good for real world economy. A carefully driven 1.2 will take you a lot further than a carefully driven TA on a tank of fuel.

Manufacturers have put their emphasis on designing for performance, not economy, because that's what most buyers want and it's what sells cars. The TA is a prime example of that; it gives impressive performance for its capacity, but an engine for the dedicated eco driver it most certainly isn't.

Just to build on what you said, the twinair was sold as an eco engine, it isn’t an eco engine.
 
Maybe it would have been better to have small engines turbos, if they didn’t cater to the lowest common denominator. As they have to make a car they will survive any manor of mechanical mistreatment.

If they were able to make an engine that had a higher tolerances and better tuning it would likely be far better in terms of economy, however would be far more highly strung and therefore likely to break down if mistreated.

It’s this very reason that supercars tend to get far better economy figures for their relative engine size than small mass market engines. A supercar is far less tolerant of a bad driver but far more effective and efficient in the way it creates power.

So the twinair actually has the potential to be a good and very efficient engine, it is those who drive them who are the problem not saying anyone on here is the problem, but 90 year old Dorris who rides he clutch and drives everywhere in 2nd gear at 20mph and alike who have to expect a certain level of performance and robustness, that means fiat have to release a car to the mass market that isn’t as good as it could be. So as highlighted in the video, they have to put things in to work around problems caused by the turbo and small engine size (such as deliberate over fueling) where as with a high (more expensive) level of refinement the engine wouldn’t need these work arounds.

But then who would pay £30,000 for a 900cc two cylinder 100hp tiny hatch back ?

I suspect the reason for the Ferrari and Maserati as well as the biposto editions of the 500 with the 1.4 multiair with much higher levels of power, help fiat refine and research better tuning set ups on their usually detuned engines. They are more highly strung cars and only bought by certain types of people not the general public.

While yes, it is people’s fault somewhat, as the video shows, you end up with a lot of performance that you can’t use without burning a lot of fuel.
 
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