Independent, Expert EV Reviews & Advice Since 2006

Has the efficiency of cars improved fast enough?

ngmw ford fiesta old and new.jpg

14 May 2013 by Paul Clarke


The many ways in which cars have improved over the last 40 years was highlighted at the recent Northern Group of Motoring Writers (NGMW)
40th Anniversary event
, when various cars spanning this time period were available to drive.

Our big question was this: has the efficiency of cars improved quickly enough over the last 40 years?

A number of manufacturers brought along historic cars, but it was Ford that put on the biggest show, with its line-up including a 1974 Granada, 1974 Capri and 1983 Fiesta. Completely coincidentally, our press car at the time of the event was the latest Ford Fiesta 1-litre EcoBoost , which naturally prompted a comparison of the efficiency of Fiestas over the years.

The Ford Fiesta first appeared in 1976, with 957cc and 1117cc engine options. In 1977 a 1297cc engine was introduced. The official fuel consumption figures given at the time were as follows: 957cc: 35.3mpg; 1117cc: 33.6mpg; and 1297cc: 31.7mpg.

In 1983 the Fiesta ‘II’ was launched, also with the same 957cc and 1117cc capacity engines, and a 1298cc unit, and it was a 1983 Fiesta II that was available for driving at the NGMW event. For this era of Fiesta, fuel economy was 43.9mpg for the 957cc engine and 37.9mpg for the 1298cc unit. A 1600cc diesel was also introduced, which returned an impressive 55.1mpg.

Here’s a comparison of the fuel economy of the smallest petrol-engined Fiestas over the years:

Engine size
Miles per gallon

1976 957cc 35.3mpg

1983 957cc 43.9mpg

1989 1100cc 33.2mpg

1996 1250cc 47.8mpg

2001 1300cc 45.6mpg

2005 1400cc 44.1mpg

2013 999cc 65.7mpg

The above figures show that there has not been a record of continuous improvement in fuel economy over the years. Only the brand new 2013 1-litre EcoBoost model can show dramatic improvement in economy compared to the previous models. One reason for this is regulation – only now do we have legislative targets to effectively incentivise car manufacturers to reduce emissions and improve fuel economy.

Improving a car’s fuel economy is not just about powertrain efficiency – there’s also another key issue: weight. Over the years cars have got heavier, and this can cancel out any efficiency improvements in powertrain technology.

A review of the weight of the Fiestas over the years – again the models with the smallest petrol engines – reveals that the 1976 Fiesta weighed 730kg; by 1983 it had climbed to 750kg; and in 1989 the Fiesta III weighed 779kg. In 1996 the lightest Fiesta had rocketed to 940kg (at the same time as it gained ugly frontal styling!). The relentless piling on of the pounds continued with the 1999 facelifted model; the scales now recorded 975kg. The new millennium brought with it the breaking of the one tonne barrier – the new 2002 model managed to weigh in at 1045kg. We had to wait until 2008 to see the first weight loss with the new, current-shape model: 965kg. However the 2013 1-litre EcoBoost Fiesta, despite its lightweight engine, can still tip the scales at somewhere between 1041kg and 1101kg depending upon specification.

Of course we know the reasons for the weight gain – much improved safety, and the motorist’s desire for ever more equipment. However weight is a key issue to be addressed from now on if car manufacturers are going to meet the increasingly tough forthcoming EU emissions targets.

So, at last, we are now seeing some real improvements to the economy of cars (ignoring the issues surrounding the flawed NEDC economy test). But what about the driving experience? Have cars moved on in 40 years?

It was certainly refreshing to drive the Mark II Fiesta, but it felt extremely basic and unrefined. Cars from three or four decades ago have a real, direct connection with the road, which comes from their light weight, and the lack of NVH work that has since been carried out to eradicate the imperfections of the road surface transmitting to the driver.

In comparison to the Mark II Fiesta, the latest 1-litre EcoBoost Fiesta felt like a highly sophisticated supercar. As well as dramatically improved economy – an improvement of almost exactly 150% over 30 years – the new car has refined and progressive performance, agile and sporty handling, and a cosseting, luxurious interior environment.

One of the other cars at the event was a 1973 Jaguar E-Type – the V12 hardtop model. With its bonnet that seemed to stretch out for miles in front of the driver, the E-Type still had a silky smooth engine and driving it was an excellent experience. However the latest 1-litre Fiesta was vastly more responsive and agile than the E-Type, had much improved braking, dramatically smoother transmission, much better overall refinement, and around 600% better fuel economy (65mpg compared to 10-12mpg). The fact that the UK’s best-selling supermini has so convincingly overtaken what was one of the world’s best sports cars in 1973 really does show progress.

But coming back to the answer to our question, although cars have improved dramatically in many ways over the last 40 years, for most of that time their efficiency hasn’t improved quickly enough. However we’re now at a point in time where manufacturers are focusing their efforts on significant improvements in economy and emissions (2012 new car emissions dropped 3.6% year-on-year to 133.1g/km CO2 – equivalent to 53.4mpg – down more than 26% since the year 2000), so it will be interesting to conduct this comparison again in 30 years’ time and see if Ford has managed to again improve the efficiency of the Fiesta by more than 150% to 100mpg. Our guess is that by 2043 they will have found a way to far exceed this level of improvement, probably thanks to unforeseen progress in the area of electric powertrains and lightweight range-extenders. The question is whether the electricity grid will have managed to achieve equivalent carbon savings by that time.

Some other cars that manufacturers brought along to the Northern Group of Motoring Writers 40th Anniversary event at Harrogate in April 2013 are shown below.

Paul Clarke


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Ford Fiesta Mark II, 1983

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Ford Capri Mark II, 1974

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Ford Granada ‘Sweeney car’, 1974

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Jaguar E-Type V12, 1973

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Jaguar XJ12, 1973 (belonged to HM the Queen Mother)

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Peugeot 504

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Renault 5