Well, not anymore.

I've long suspected that the TA's relatively poor MPG was a result of the official test being performed on 14" steel wheels and 175 tyres, while most buyers of TA's seem to go for Sport or Lounges with big 16" wheels and far too heavy 195's.

So I finally fitted that brand new set of Pop wheels and tyres.

Results? My best previous tank was 4.7/100km (60mpg imp)

With 100km on the new rubber so far, I'm seeing 4.1l/100km (68mpg).

On a 7km trip to the post office in moderate traffic, I scored 3.2l/100km (88mpg) - the return leg scored 3.5l/100.

The best part? This was all done without any extreme driving techniques, no coasting in neutral, no engine off, no fancy instruments. Just accelerating and keeping up with the traffic. The only basic ecodriving technique used was not to use the brakes, with a car as chuckable as a 500, even if you're out for a good fang, there's really no need for that pedal.

The results are a bit preliminary so far, I've posted because it might take me six months to finish the fuel left in the tank! A 1000km tank is almost in reach.

Very interesting indeed.
Well done, and I look forward to further figures.

Our 500TA has alu multispokes with Goodyear 185/55/15, so I wonder what you now recommend I should replace ours with come the day they wear out ...... may not be long now.

UFI said:

So I finally fitted that brand new set of Pop wheels and tyres.

Click to expand...

Pardon my ignorance, but what wheel/tyres are they?

Thanks,
Mick.

Eco on or off?

Mick F said:

Very interesting indeed....... may not be long now.Pardon my ignorance, but what wheel/tyres are they?

Click to expand...

They're ContiEcoContact 3's. Bear in mind that in my case there are three factors at work, and I swapped near new tyres for new tyres.

A: I've saved about 3kg per wheel/ tyre (loosely equivalent to 36kg of dead weight)
B: The plastic wheel covers and narrower tyres improve aerodynamics
C: The tires have less rolling resistance

As a guide 'B' is probably worth 4mpg, with A and C worth about 2mpg each. Because MPG improves as tyres wear and age, switching to an Eco tyre may not actually see an immediate improvement vs old. Having said that, Goodyear seem to have very poor MPG across the board. I have a set of 'Eco' Goodyears on my trailer that only score an 'E' on the EU tyre label (they're car tyres not commercial tyres).

Unfortunately the plastic wheel covers have ruined UFI's looks, in the long term I want a set of light forged 15's, but nothing will match the MPG of what I'm running now. I'm toying with getting a set of baby moon's but mine's a 'Sport' with no chrome trim (and a black roof), so it won't look as cohesive as they would on a Pop or Lounge.

Mercky said:

Eco on or off?

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The US EPA tested a BMW M5 in 400hp mode vs 500hp mode and found no discernible difference to fuel consumption. Eco mode on the Fiat is really only useful for people who can't help themselves

I actually do use it on long trips as I find the amount of throttle needed to cruise a bit more comfortable than having the pedal closer to vertical. But overall, I'd rather have the power when I want it, as I do accelerate fairly 'briskly'.

Thanks.

I often wonder about the Eco button.
Why have it?
Yes, it makes the car easier in town and traffic. Steering is very easy and throttle response is gentle.

However, in Normal mode, you don't have to use all of the 85bhp all the time. So why not just ease up a bit?

Constant speed of (say) 50mph in Eco must use the same fuel in Normal at the same speed. Same car, same road, same conditions. You still have to propel the vehicle, so it matters not which mode you are in with respect to economy.

Regards,
Mick.

In ECO at higher speeds the engine needs to work harder, so I agree ECO can be turned off. For town driving ECO is excellent or times when you really don't care to drive and need to get from A to B.

Its easy to average 55mpg when the car is loosened up a bit, but the above MPGs are fantastic.

Mick F said:

I often wonder about the Eco button.
Why have it?
Yes, it makes the car easier in town and traffic. Steering is very easy and throttle response is gentle.

Click to expand...

Fiat claim Eco mode changes the UniAir systems performance (which controls valve lift, timing and duration) so theoretically, Eco is like switching to an Eco camshaft (as was popular with Eco specials in the 90's). Eco is said to make the engine smoother/ more tractable at low rpm. In the real world, you're likely to just use more throttle/rpm and offset any savings (more RPM, more frictional losses). Around town, the lighter steering on Eco means more power drawn from the battery.

UFI just clicked over 9000km from new, so I'd say it's only half way run in. I suspect Eco might be more effective on a fully run in car with light loads (no passengers - narrow wheels etc). I have six months of warranty left, after that I'm fitting a dedicated accurate fuel computer and I can test all my hypotheses.

Mick F said:

I often wonder about the Eco button.
Why have it?

Click to expand...

I reckon the Eco button is actually most useful for Dualogic cars as it ensures that the car stays in higher gears longer before changing down. With Eco off, my Dualogic loves to change down to 2nd gear while trundling around the suburbs, which really destroys fuel economy.

I find the Eco light steering is a bit too light. Something in the middle would've been nice.

Ah, that would make a big difference.

In order to get better economy with a manual in Eco mode, you need to drive economically too. The "lack" of power just means you press the Go pedal further if you're not careful.

I notice with our manual 500TA that the "shift" notification on the dash is at much lower revs. It's worth taking notice of it and doing as I'm told.

Regards,
Mick.

UFI said:

Well, not anymore.

I've long suspected that the TA's relatively poor MPG was a result of the official test being performed on 14" steel wheels and 175 tyres, while most buyers of TA's seem to go for Sport or Lounges with big 16" wheels and far too heavy 195's.

So I finally fitted that brand new set of Pop wheels and tyres.

Results? My best previous tank was 4.7/100km (60mpg imp)

With 100km on the new rubber so far, I'm seeing 4.1l/100km (68mpg).

On a 7km trip to the post office in moderate traffic, I scored 3.2l/100km (88mpg) - the return leg scored 3.5l/100.

The best part? This was all done without any extreme driving techniques, no coasting in neutral, no engine off, no fancy instruments. Just accelerating and keeping up with the traffic. The only basic ecodriving technique used was not to use the brakes, with a car as chuckable as a 500, even if you're out for a good fang, there's really no need for that pedal.

The results are a bit preliminary so far, I've posted because it might take me six months to finish the fuel left in the tank! A 1000km tank is almost in reach.

Click to expand...

Funny thing is I've said this many times and people act like you've got two heads. It makes a noticeable difference in acceleration in a 1.2, probably less noticeable in a Twinair.

If you want to gain a mpg or two, lower your car I put B14's on about a month ago and it's a tiny bit more economical. Previously my best economy on the way to work was about 62mog and recently I've been getting 64 or so. On steelies and winter tyres it can get 70mpg. Replaced my thermostat today as well as the housing had cracked, have discovered that the stat was slightly open regardless of temperature, should get slightly better economy now as well

306maxi said:

Funny thing is I've said this many times and people act like you've got two heads. It makes a noticeable difference in acceleration in a 1.2, probably less noticeable in a Twinair.

If you want to gain a mpg or two, lower your car I put B14's on about a month ago and it's a tiny bit more economical.

Click to expand...

Funnier thing is I'm getting exactly the 8mpg you suggested

I fully intend on getting on getting B14's but on a car that does 3,000km a year it will be a while before I get my monies worth out of the stock set up. Alternatively I could do it soon and try to sell my low km originals.

UFI said:

Funnier thing is I'm getting exactly the 8mpg you suggested

I fully intend on getting on getting B14's but on a car that does 3,000km a year it will be a while before I get my monies worth out of the stock set up. Alternatively I could do it soon and try to sell my low km originals.

Click to expand...

To be fair on Perth roads they'll probably last an age. My passenger side front had spunked more or less all of its oil out.

I've got mine set at max ride height so they're preloaded to the max, it's a bit stiff but not unpleasant. Looking forward to seeing if a properly functioning thermostat makes a difference.

UFI 306maxi

Yes I agree the B14's help mpg a bit especially at high speeds.
The steel wheels an 14 175's absolutely. The 195's are way too wide for the fiat and ruin it. I estimate I have improved my fuel mileage by 0.5l/100 km just by going from 195's to 185 fuel saver's without changing the wheels themselves.

Who knows UFI, maybe they even went 165 for the official fuel mileage test = )

ahmett said:

Who knows UFI, maybe they even went 165 for the official fuel mileage test

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In 1.2 form, the 500 is over tyred.

My Panda runs 155 as standard and that has near-identical performance & handling to the original 1.2 500 (before the rear axle mod). My 500 handbook lists 165's, but only for use on versions without power steering.

Tbh the car would likely ride & handle just fine on 135's.

Lowering isn't an option for me as I need all the ground clearance I can get. I'm curious if it would help if Fiat were to streamline the underside of the car - mine doesn't even have an undertray. I doubt you could do much else with the aerodynamics without spoiling the appearance - and without that, I doubt Fiat would sell even 20% of the 500's they do.

jrkitching said:

In 1.2 form, the 500 is over tyred.

My Panda runs 155 as standard and that has near-identical performance & handling to the original 1.2 500 (before the rear axle mod). Fiat list 165's for the 500, but only on versions without power steering.

Tbh the car would likely ride & handle just fine on 135's.

Click to expand...

Depends on the way you drive, I had to correct my slide and brake to not under steer off the road on my 185 eco's. If I had my sticky Michelin 195 pilots, that wouldn't have happened !

jrkitching said:

In 1.2 form, the 500 is over tyred.

My Panda runs 155 as standard and that has near-identical performance & handling to the original 1.2 500 (before the rear axle mod). My 500 handbook lists 165's, but only for use on versions without power steering.

Tbh the car would likely ride & handle just fine on 135's.

Lowering isn't an option for me as I need all the ground clearance I can get. I'm curious if it would help if Fiat were to streamline the underside of the car - mine doesn't even have an undertray. I doubt you could do much else with the aerodynamics without spoiling the appearance - and without that, I doubt Fiat would sell even 20% of the 500's they do.

Click to expand...

My 500 isn't that low tbh. With better damping it doesn't wobble all over the place and IMHO is less likely to hit anything. It's at maximum ride height so it's lost maybe 20 or 30 mm at most.

306maxi said:

My 500 isn't that low tbh. With better damping it doesn't wobble all over the place and IMHO is less likely to hit anything. It's at maximum ride height so it's lost maybe 20 or 30 mm at most.

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Yes, the damping is the greatest weakness in the factory-fitted suspension.

Whilst any 500 would no doubt benefit from B14's, do you think the difference would be less noticeable on the later cars with the revised rear beam?

I'd also suggest the difference will be more obvious if you're doing the upgrade to a car with significant mileage, simply because the original suspension will be that much more worn.

also, in terms of fuel economy the 500 is overtyred on 16's. With good suspension though it can exploit that extra grip and do fun things

Maybe we'll see more manufacturers going down the route BMW has taken with the i3 and go for skinny tyres with big wheels for efficiency.

jrkitching said:

Yes, the damping is the greatest weakness in the factory-fitted suspension.

Whilst any 500 would no doubt benefit from B14's, do you think the difference would be less noticeable on the later cars with the revised rear beam?

Click to expand...

The damping is still bad on all 500's. I've a journalist friend who drove an abarth and bemoaned the complete lack of suspension.

306maxi said:

Maybe we'll see more manufacturers going down the route BMW has taken with the i3 and go for skinny tyres with big wheels for efficiency.

Click to expand...

Skinny tyres, certainly.

Not so sure about big wheels, though, as this increases the rolling inertia (and thus the effective mass of the car). Perhaps not so much of an issue on an electric vehicle will full regenerative braking, but on a normally braked car, I'd want the wheels as small as possible to keep the rolling inertia down.

Streamlining the wheel covers helps, too - the multispoked things on some alloy wheeled 500's are effectively a set of retardation fans.

This is a good place to start if you want to look at the issue from a more technical perspective.