Technical Newbie with a reversing Twin Air query!

[AGH1965]

I reckon that no car would be happy in 4th gear and having the throttle floored.

Why not? I tried this recently with a new Mazda 2 with 90 hp 1.5 SKYACTIV engine. Not a single problem, not even in 5th gear and starting the acceleration from 800 rpm. (Why did I try this? I was looking for a new car for my wife. She has the habit of using the wrong gears. Therefore a 500 with TA isn't suitable for her.)

 

[Mick F]

Why not? I tried this recently with a new Mazda 2 with 90 hp 1.5 SKYACTIV engine. Not a single problem, not even in 5th gear and starting the acceleration from 800 rpm.

OK.
I stand corrected!

Never tried it for years and years. It used to be a good way to check for worn big-ends. Last time I tried it was possibly when I was test-driving a Hilman Hunter back in 1975

I'm too sympathetic to my cars, so rarely stress them, but in the interests of science and this forum, I'll experiment later this week. Not many flat roads round here, but I'll find somewhere.

Stand by for my report.
Mick.

 

[Mick F]

Blonde?
I'm very grey and very thin on top!

Ok, I'll get into 4th and slow right down to 1000rpm(?) and try and accelerate away.

Maybe not tomorrow or Wednesday, but by the end of the week. I don't drive every day, but next time out I'll try it.

Actually, I was out this afternoon and I carried out an experiment a few times.

As I said, there aren’t many flat places around here, so I had to make do with what I could find.

Remember, ours is a 500TA 2001 Euro5 and without a DM flywheel.

Slowing right down in 4th gear to 1000rpm, I floored the throttle. I did this a few times on different bits of road on slightly different inclines but got similar results. I also slowed to slightly above 1000rpm and slightly below 1000rpm. The difference in the revs were the thickness of the rev counter needle. How accurate the rev counter is, I ain't got a clue, and how accurate I carried out my experiments, I cannot say, but I did it as well as I could.

Results?
I can honestly say that flooring the throttle in 4th gear seemed quite normal and I would have expected a small engine to react. It vibrated a bit, and then went on without complaining and accelerated away quite well. The vibration wasn't harsh or alarming, the car didn't vibe off the road, or make some awful grorching noise.

If I tried it a needle's-width below 1000rpm, the engine did not much. I vibrated and struggled and nearly stalled. A needle's width above 1000rpm, the engine didn't vibrate at all and accelerated smoothly and evenly.

The 1000rpm barrier is crucial to smoothness and power. Below and it can't do it at all, above it, and it's fine, and smack on it thinks about it but is ok.

At no time did the car feel as it it was under torture or seem to vibrate itself to bits.

Thanks and regards,
Mick

 

[AGH1965]

Mick, I did the following experiment with both my previous 2011 500 with Euro 5 TA and my current 2014 500 with Euro 6 TA:

• Drive in 5th gear in normal mode, i.e. non eco mode, on a level road.
• Remove right foot from accelerator pedal.
• Wait until speed reaches 50 km/h (31 mph) on the dashboard.
• Floor accelerator pedal instantly.
• Ignore the gear shift indicator while accelerating.

The difference between the two cars is huge. With the Euro 6 TA the engine vibrates, but with the Euro 5 TA the engine shakes so heavily that it's almost frightening.

Most likely that the difference is caused by the different flywheel.

 

[Mick F]

[*]Drive in 5th gear in normal mode, i.e. non eco mode, on a level road.
[*]Remove right foot from accelerator pedal.
[*]Wait until speed reaches 50 km/h (31 mph) on the dashboard.
[*]Floor accelerator pedal instantly.
[*]Ignore the gear shift indicator while accelerating.
[/LIST]The difference between the two cars is huge. With the Euro 6 TA the engine vibrates, but with the Euro 5 TA the engine shakes so heavily that it's almost frightening.

OK.

I'll try that, but finding somewhere level locally on a suitable road for experimentation to do this in 5th, maybe a bit difficult. Anyway, I'll try.

Going along in 5th, then taking the foot off generally results in a long tail-off in speed. There's not much engine-braking with a TA.

Anyway, as I say, I'll give it a go when I can.

Regards,
Mick.

 

[ahmett]

Mick, I did the following experiment with both my previous 2011 500 with Euro 5 TA and my current 2014 500 with Euro 6 TA:

• Drive in 5th gear in normal mode, i.e. non eco mode, on a level road.
• Remove right foot from accelerator pedal.
• Wait until speed reaches 50 km/h (31 mph) on the dashboard.
• Floor accelerator pedal instantly.
• Ignore the gear shift indicator while accelerating.

The difference between the two cars is huge. With the Euro 6 TA the engine vibrates, but with the Euro 5 TA the engine shakes so heavily that it's almost frightening.

Most likely that the difference is caused by the different flywheel.

yeah we have a Euro 5 TA Lancia Auto, 50 kmh is too slow in 5th for it, in comparison with my 500 1.4 Auto which is fine cruising along at 50 kmh in 5th.

 

[UFI]

Bearing in mind that driving a DMF equipped car in the low speed 'vibration zone' may cause premature DMF failure.

I think UFI's non DMF is still too smooth... now where can I get a lightened flywheel?

 

[Mick F]

.......... now where can I get a lightened flywheel?

When I was modifying my Mini - 100bhp, 1400cc, Powermax pistons, balanced bottom end, vernier duplex timing gear, road/rally cam, ported head, huge SU carb with KN filter, long centre-branch manifold and straight-through exhaust, taller diff, competition clutch ....................

............ and lightened flywheel.

Me and a mate got it onto a lathe in his factory and we turned off POUNDS of steel. Can't remember the weight difference, but obviously we took off metal from the outer area to reduce the rotating weight.

It made a huge difference to the engine pick-up and the way the engine performed.

Regards,
Mick.

 

[AGH1965]

Bearing in mind that driving a DMF equipped car in the low speed 'vibration zone' may cause premature DMF failure.

Good point! Therefore I emphasise that I don't encourage anyone to do the experiment that I described above! I only described it to demonstrate the difference between the 500 with Euro 5 TA and the 500 with Euro 6 TA.

 

[AGH1965]

we have a Euro 5 TA Lancia Auto, 50 kmh is too slow in 5th for it

Your right, but the gear shift indicator of my 2011 500 with Euro 5 TA85 advised me to drive 50 km/h (on the dashboard, so approximately 45 km/h in reality) in 5th gear when in eco mode...

 

[Mick F]

Mick, I did the following experiment with both my previous 2011 500 with Euro 5 TA and my current 2014 500 with Euro 6 TA:

• Drive in 5th gear in normal mode, i.e. non eco mode, on a level road.
• Remove right foot from accelerator pedal.
• Wait until speed reaches 50 km/h (31 mph) on the dashboard.
• Floor accelerator pedal instantly.
• Ignore the gear shift indicator while accelerating.

The difference between the two cars is huge. With the Euro 6 TA the engine vibrates, but with the Euro 5 TA the engine shakes so heavily that it's almost frightening.

Just come in from shopping in Tavistock, and on my way home I conducted your experiment. I did it four times, twice in one direction, then twice in the other .............. along this road.
https://www.google.co.uk/maps/@50.5...03&h=100&yaw=79.934631&pitch=0!7i13312!8i6656

I can honestly say ......... and you can believe me or not .......... that there wasn't a problem at all. I was quite brutal with the Go pedal and floored it suddenly and without mercy.

At 30mph the rev counter was showing 1200rpm in 5th and at those revs, it's fine.

Lastly, I tried one further go at 1000rpm in 5th and it wouldn't react, it just grumbled.

Either there's something wrong with our 85hp TA engine, or there's something wrong with yours, but I can assure anyone reading this that our 85hp TA didn't complain at all. It told me to change down, but hardly batted an eyelid.

Regards,
Mick.

 

[TrevC]

My 2011 TA Lounge certainly vibrates if you try to accelerate, even gently, from 30mph in 5th with Eco on. Undriveable at that speed in 5th with Eco off.

 

[jrkitching]

My 2011 TA Lounge certainly vibrates if you try to accelerate, even gently, from 30mph in 5th with Eco on. Undriveable at that speed in 5th with Eco off.

The Euro5 1.2 will do this easily, though not quite as easily as the Euro4 1.2 in the Panda.

At these speeds in 5th gear, even a small gradient (either way) makes a big difference.

 

[AGH1965]

Either there's something wrong with our 85hp TA engine, or there's something wrong with yours

Or FIAT changed something between 10/2/2011 (production date of my previous 500) and 28/7/2011 (production date of your 500).

Interesting result, Mick. With my car I felt the whole engine shaking massively at a frequency between 1 and 2 Hz.

So the behaviour of my previous 500 had probably nothing to do with the absence of a dual mass flywheel.

Mick, just to be sure, did you kick the pedal down as quickly as possible, so in approximately 0.1 s?

 

[AGH1965]

My 2011 TA Lounge certainly vibrates if you try to accelerate, even gently, from 30mph in 5th with Eco on. Undriveable at that speed in 5th with Eco off.

Hey, that last part is interesting. So my 2011 TA wasn't the only one behaving terribly in that situation?

 

[Mick F]

Yes, I did.
I stamped on the throttle.

Just been doing some housework. Notice I'd just done the shopping?
These are the joys of being retired whilst Mrs Mick F is at work!

Whilst doing the chores, it occurred to me that there is something else to consider here. I changed the spark plugs in September, and immediately I noticed how much smoother the engine ran. I put it down to the fact that the plugs were tired and old, and new ones restored the engine to what it SHOULD have been.

Since then, the car runs sweeter, quieter, nicer .......... but I've not noticed any increase in economy, sadly.

I wonder, if I'd have done the experiment with the old plugs in, that I could have had a violently shaking engine during my experiments.

For the record, here is the thread I was involved with:
https://www.fiatforum.com/500/428208-twinair-spark-plugs.html

Now I have the old plugs out, I see they are numbered 55233997
New plugs from Shop4Spares is 55242187

Does this make any difference?
They are visually identical.

Also the old plugs have a spark gap of 31thou (as measured with my elderly feeler gauges) and the new ones at 25thou. Hopefully, the difference is because of the old ones having done 18,500miles.

As I say, since fitting these new ones, the engine runs as sweet as a nut.

TTFN
Mick.

 

[UFI]

Part of it comes down to your wheel and tyre selection, slight gradients, road surface, prevailing winds and so on. UFI will happily trundle along in top at 50, but I don't think going hard WOT from such speeds would be a smooth experience.

My 1.6 petrol Renault is quite happy pulling two tons in top gear from 38km/h...Nothing really to do with the discussion at hand but I still find that impressive.

 

[Mick F]

Yes, our 1.6 16v Clio is a delight to drive. You can select 5th gear and it just goes! That engine is beautiful.

Trouble is, it cost £205 per year in VED even though it returns 50mpg on a long run and 40mpg locally.

I reckon our 500TA only gets 5mpg better comparing speed for speed and journey for journey with us and it costs zero VED.

However, the Clio drinks petrol if you get above 80 on the motorway. Maybe only gets 30mpg at 85mph.

Regards,
Mick.

 

[typecastboy]

So, I've bought my second Twinair today. 2011 Lounge. My first one one made this horrible noise, and lo and behold so does this one.

I can't believe that Fiat fob people off with it being a quirk of the car. I don't know whether mine has a DPF or not. Ridiculous noise, but something we just have to put up with. Car drives lovely, just don't want to drive it backwards.