General Twinair - Rubbish mpg with City Driving

[pearce_jj]

As an engineer, I don't believe the philosophy behind this engine design is conducive to maximising economy - it has too many moving parts for one thing, and a turbo for another

I recently bought a Skoda with their small petrol turbo (1.2tsi) which seems to be returning 44mpg cruising at 70mph and about 35mpg around town. Considering that is a bigger and heavier car with more power and twice as many cylinders, I'm at a bit at a loss as to why the TA isn't return (a lot) more.

 

[jrkitching]

As a 1.4 driver that has difficulty in showing restraint I would not do too well in a TA - it will be on boost whenever the open road is shown to me. I have to leave the Sport button off on the 1.4 to slow down. On the test drives & the reviews that I have read - I reckon I would average 38mpg so that would better a 1.4 by 3mpg. I'm making presumptions here - I hope that's OK .

That's exactly the sort of comparison that would make sense; the TwinAir is the logical successor to the 1.4, not the 1.2. I too would expect the TwinAir to beat the 1.4 in real world driving; however enthusiastic you are, you can't drive fast all the time & in your more restrained moments the TwinAir should compare favourably.

 

[ahmett]

Wow i cant believe the twinair is only 200 pounds cheaper than the 1.4. And the 1.4 comes with ESP and rear discs as standard! So no thank you = ) Big deal if it is a 'bit' more economical we are talking a difference of what 5 mpg? (ok if you live in london get the twinair of course) If i would get the twinair it would have to be the 105 hp version whenever that comes out and it would have to be priced competitively with the 1.4!

 

[highisland]

I got the TA because it now costs me only £10pa to enter the Congestion Zone.
I don't understand why anybody outside of London would want one.

Not that I do, but 250 days x £10 (with autopay it's £9) = £2,500 which adds up to considerable savings regardless of mpg.

 

[RobinPJ]

I got the TA because it now costs me only £10pa to enter the Congestion Zone.
I don't understand why anybody outside of London would want one.

Not that I do, but 250 days x £10 (with autopay it's £9) = £2,500 which adds up to considerable savings regardless of mpg.

For how long I wonder?

 

[loveshandbags]

Wow i cant believe the twinair is only 200 pounds cheaper than the 1.4. And the 1.4 comes with ESP and rear discs as standard! So no thank you = ) Big deal if it is a 'bit' more economical we are talking a difference of what 5 mpg? (ok if you live in london get the twinair of course) If i would get the twinair it would have to be the 105 hp version whenever that comes out and it would have to be priced competitively with the 1.4!

My experience of Turbo charged cars was that it gave the best BHP is when the weather is cold. (this contradicts the impact on MPG when its cold on the TA). I remember a guy with a MX5 BBR turbo in Lanarote saying that his car ran too hot and the boost would retard. He said that he would have been better off with a bigger cc engine (the 1.8) and as opposed to boosting his 1.6

So your 1.4 Euro 5 S/S with no congestion charge in Greece IMHO is the right choice.

 

[highisland]

For how long I wonder?

True, it could be dis-exempted. But even over a single year, the savings are decent.

 

[RobinPJ]

True, it could be dis-exempted. But even over a single year, the savings are decent.

Oh I agree - I was not questioning your logic at all. It is just that policitians will move the goalposts whenever it suits, and the eco-warrier bandwagon means that motorists are a soft option with no one likely to feel sorry for them.

 

[pearce_jj]

This is very true - the original 1.3MJ was supposed to be FOC for congestion charge and road tax, however the bands then got changed. Maybe that promise was the reason the original 111g/km rating was soon revised to 110g/km (through unknown means).

 

[cjc156]

I don't understand why anybody outside of London would want one.

.

Where as my opinion is, I don't understand why anybody wouldnt want one....

As previously mentioned in this thread it should be looked at in comparison to a 1.4 not a 1.2

 

[TrevC]

Quite - then there's the noise it makes when you accelerate - brilliant! To be fair, I didn't try the 1.4 and I'm sure it's a fine car. Also, the twin-cylinder engine won't be to everyone's taste. From the outside it sounds like a diesel at idle, and a 4-cyl will always pull more smoothly from low rpm. Like everyone keeps saying, you have to try them all and pick the one you like/can afford.

 

[birmint]

Where as my opinion is, I don't understand why anybody wouldnt want one....

I'm 900 miles into mine and would agree but I guess its a bit like marmite - you either get it or you dont and which ever way you lean is neither right or wrong!

I am seriously hooked with mine from the fact that mechanically its so different to anything else. The noise is an added benefit. I'm a car nut and am fortunate there is a choice of keys on the rack but always pick up the 500. Appreciate its still a bit of a novelty... Although the congestion charge exemption is a major benefit to me I think the car performs better out of town without having to navigate the ridiculous speed bumps and crater sized potholes in central london. The week I had in rural Devon with it seemed an ideal match - narrow lanes, hills etc - was perfect.

Lots of folks appear from no where to remark on the colour and the roof etc. One woman said it looked so good she wanted to to lick it .... I did have to double check she was talking about the car Sorry cheap joke... but true.

 

[D4nny8oy]

I remember a guy with a MX5 BBR turbo in Lanarote saying that his car ran too hot and the boost would retard. He said that he would have been better off with a bigger cc engine (the 1.8) and as opposed to boosting his 1.6.

As long as the intercooler is efficient, and the boost hasn't been cranked-up, a turbo'd car will cope happily with high ambient temps.

Anyway- if you're trying for economy, you won't be pushing the turbo hard enough to generate high intake temps.

 

[loveshandbags]

As long as the intercooler is efficient, and the boost hasn't been cranked-up, a turbo'd car will cope happily with high ambient temps.

Anyway- if you're trying for economy, you won't be pushing the turbo hard enough to generate high intake temps.

In the case of the chap over in Lanzorote he claimed to have cranked the boost up. Not only was his car running 'hot' his gearbox was starting to grate. There has been a recent revival of old MX5 BBR turbo and it's interesting to note on the new setup they're placing the intercooler in front of the rad
http://www.classicandperformancecar.com/news/octanenews/262246/first_drive_mazda_mx5_bbr_turbo.html
possibily to allow the intercooler to run more efficiently. I had a particular interest in this because I had a MX5 (put in a Jackson CAI - very successful) and on the RS Turbo used to BBR chips on the Phase II the boost started to retard towards the latter half of the journey - could have been down to the intercooler not been big enough.

On the cold temperature thing I couldn't find the picture that I had seen of track guys racing around in turbo charged cars in the snow with ice specially studded tyres - all I could find was this (not so exciting) one but I would bow to the depth of your technical knownledge since I have no mechanical training.
http://forums.tdiclub.com/showthread.php?t=65676

 

[cjc156]

At the risk of making myself unpopular....

As I've mentioned my TA was in the garage today as part of a recall (for the turbo). So I was loaned a 1.4 Sport (pre ARB) model. After some varied miles, my conclusion is the TA is a superior car. In summary I'd say:-
- The TA engine is faster on the road than the 1.4, probably not quicker away from the lights, but in real world driving it certainly seems it
- The 1.4 showed 37 mpg on the trip B over 12000 miles and was around that for the miles I did
- The TA is a Pop and rides better over undulating county roads, I know this one was pre ARB but the difference again was significant. The TA settles down much quicker and doesn’t fidget like the 1.4 did

It really did feel like two completely different cars when driven on the same road in close succession.

 

[306maxi]

At the risk of making myself unpopular....

As I've mentioned my TA was in the garage today as part of a recall (for the turbo). So I was loaned a 1.4 Sport (pre ARB) model. After some varied miles, my conclusion is the TA is a superior car. In summary I'd say:-
- The TA engine is faster on the road than the 1.4, probably not quicker away from the lights, but in real world driving it certainly seems it
- The 1.4 showed 37 mpg on the trip B over 12000 miles and was around that for the miles I did
- The TA is a Pop and rides better over undulating county roads, I know this one was pre ARB but the difference again was significant. The TA settles down much quicker and doesn’t fidget like the 1.4 did

It really did feel like two completely different cars when driven on the same road in close succession.

Turbo engines will always seem quicker than they actually are The 1.4 needs revs to do its thing

 

[loveshandbags]

At the risk of making myself unpopular....

As I've mentioned my TA was in the garage today as part of a recall (for the turbo). So I was loaned a 1.4 Sport (pre ARB) model. After some varied miles, my conclusion is the TA is a superior car. In summary I'd say:-
- The TA engine is faster on the road than the 1.4, probably not quicker away from the lights, but in real world driving it certainly seems it
- The 1.4 showed 37 mpg on the trip B over 12000 miles and was around that for the miles I did
- The TA is a Pop and rides better over undulating county roads, I know this one was pre ARB but the difference again was significant. The TA settles down much quicker and doesn’t fidget like the 1.4 did

It really did feel like two completely different cars when driven on the same road in close succession.

Good posting.
The real test is - will they have a 3 year old TA as a loan car.

 

[D4nny8oy]

There has been a recent revival of old MX5 BBR turbo and it's interesting to note on the new setup they're placing the intercooler in front of the rad

Where were they putting them before? Surely not behind the radiator with 90+deg coolant temps flowing through them?

 

[306maxi]

Where were they putting them before? Surely not behind the radiator with 90+deg coolant temps flowing through them?

Maybe they were liking the Nissan Sunny GTi-R interwarmer location?

 

[loveshandbags]

Where were they putting them before? Surely not behind the radiator with 90+deg coolant temps flowing through them?

I didn't have one fitted to my MX5 but the article seems to imply that it was in the wrong place. It might explain what the your man's car ran hot

http://www.classicandperformancecar.com/news/octanenews/262246/first_drive_mazda_mx5_bbr_turbo.html
Time moves on, however, especially with electronics. BBR still uses its own ‘Interceptor’ ECU to fool the standard item into delivering the fuel and ignition settings the turbo engine requires, but today’s version is much smaller and cleverer. The mechanical part has changed too, with a Garrett GT25 twin-scroll, ball-race turbocharger instead of the old T25, mounted on a new manifold with split downpipes. And the intercooler now sits ahead of the radiator, which involves the bumper-dismantling Mazda’s dealers wanted to avoid back in the day.