The PSA 1.6 HDi, TDCi, DRIVe engine is widely used in various Peugeots, Citroens, Fords, Mazdas and Volvos. What I can't get my head around is the pretty large variance in CO2 emissions and economy for what is essentially the 'same' engine.
Volvo seem to have done the best job of getting the CO2 down and the economy up, which is surely what many are wanting from either a private or company car these days. To take the V50 Volvo estate as representative, they manage to get the following out of it, probably with some clever electronic trickery from the ECU. Probably nothing like this in real life, unless you happen to commute to work in a laboratory and your route is uncannily similar to the EC economy test route:-
Economy = 74.3 mpg
Emissions = 99 g/km
For the brand new Focus estate, which I guess is broadly similar in terms of size, Ford can 'only' extract:-
Economy = 67.3 mpg
Emissions = 109 g/km
Both of the above have very similar power and torque outputs.
There isn't a comparable Mazda estate, but the smaller Mazda3 hatchback only posts:-
Economy = 64.2 mpg
Emissions = 117 g/km
Peugeot's 308 estate with the 'low power' 90ps version gives a pretty poor:-
Economy = 68.9 mpg
Emissions = 123 g/km
I guess one key is the use of 'stop/start' on the Volvo, but I'd be surprised if Volvo, who I imagine have effectively bought this unit off the shelf from PSA have developed their own stop/start system.
Peugeot/Citroen seem to be going down the dreaded 'automated manual' gearbox route with the C5 and 508, in order to get the emissions down to levels that are still higher than the Volvo. Admittedly both of the above are bigger vehicles though.
Interesting mix of 5 and 6 speed gearboxes for the above examples, with the Volvo using a 5 speed 'box to best effect.
Although Ford will launch an Econetic version of the Focus in due course, for a brand new car, I'm surprised they haven't got the emissions down a bit more for their diesels. The 2.0 TDCi looks particularly poor at 129 g/km for the 140 ps unit. VW have got this down to 114 g/km for the 2.0 TDi 140 ps Golf, when coupled to their Bluemotion Technologies fancy stuff. The above difference makes for quite a bit more company car tax payable on the Focus.
Any thoughts?
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Official economy figures should always be taken with good salt pinch.
When owners have calculated their brim to brim usage, whilst neglecting to factor in the very real 10% or so speedo (therefore odo?) error in most cases, those official figures seem far from the truth.
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>> When owners have calculated their brim to brim usage, whilst neglecting to factor in the
>> very real 10% or so speedo (therefore odo?) error in most cases, those official figures
>> seem far from the truth.
The speedo is calibrated to be inaccurate, the odo is usually remarkable accurate, the ones I have checked with Sat Nav are anyway.
But back to the Original question about economy figures. It depends on how and where you drive it. I have been experimenting with the Lancer, and brim to brim, I can get 35mpg and recently I got 46mpg. (that was an excessive lorry drafting mimsing exercise tho) Its published figure is 41,
To get 41 it has to be almost 100% motorway cruise.
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>> >> Any thoughts?
>>
And BMW get 125g/km for the 177bhp 120d and 135g/km for the 204bhp 123d.
Ford were leading the diesel brigade with the first CR TDCI's in '01 and kept pace with the PSA joint venture units though the PSA/Ford units have been left behind a little in efficiency terms by BMW and latterly VAG since they adopted CR.
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Too simple to expect the same engine to give same figures.
Weight, aerodynamics, gearing and engine mapping ( perhaps to overcome the aforementioned things ) all contribute - I recall seeing that a Prius looses a few mpg just by nature of having alloy wheels rather than the narrower steel ones.
Try getting the aero info on those cars and do a power-to-weight ratio check to see if theres any pattern. I remember the Citroen CX used to be pretty thirsty around town but due to its aero superiority was especially frugal at higher speeds. Even the petrols.
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Weird, it doesn't look like there's much difference in engines, differences are weight and top speed - interestingly both higher in the Volvo!
Higher top speed with the same bhp suggests aero factors i think?
Metric |
v50 1.6 Drive 2011 model |
Focus Estate Edge 1.6 2011 model |
|---|
Weight | 1413 kg | 1368 kg |
0-60 | 11.1 secs | 10.7 secs |
Top Speed | 121mph | 120mph |
Power | 113bhp (no rpm data though!) | 113bhp |
Torque | 199lb/ft (no rpm data though!) | 199 lb/ft |
MPG | 74 | 67 |
Emissions | 99g/km | 109 g/km |
Drag Coefficients | 0.29 | 0.27 |
Some of the data must be wrong. Are Volvo not prone to cheating on tests? I remember reading on here they had submitted a car for the MPG tests with smaller / lighter wheels than available for a customer to buy.
Last edited by: Skoda on Sun 8 May 11 at 12:03
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There's a thread somewhere on here where on of the Khoo guys grumbled that his Volvo wouldn't get anywhere near the figures.
Here it is...
www.car4play.com/forum/post/index.htm?f=1&t=881
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Just an observation, take the manufacturers' figure with a huge pinch of salt. I appreciate that the published CO2 figures are important for BIK if it's a company car but if the actual economy matters to you then do your research / get a long test drive before buying. I've a hunch the 2.0l Volvo V50 will give better real world economy than the 1.6DrivE.......
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These engines vary wildly. We eventually got to the bottom of why SWMBO's car (C4GP) was only getting 37mpg. The air mixer box was leaking. It was only when it started blowing oil residue onto the piping between the turbo and the intercooler would Citroën do anything about it. They took off the plastic box and resealed it with what looks like bathroom sealant.
Seems to have done the trick as the car is now averaging what Citroën claim. Pity it took so long and so much extra CO2 into the environment to discover it.
The whole reason for buying the car was the claim of the lowest CO2 rating of any 7 seater at the time. had I known it would only deliver 37mpg I would have gone for an XC90 D5 auto.
Last edited by: gmac on Sun 8 May 11 at 18:21
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The Volvo must run on Red Bull :-)
Looking at those figures, one has to assume its gearing or some engine mapping difference that is more successful.
I found the 207 diesel was certainly economical but also anemic compared to older diesels, however it cruised very easily indeed.
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my c3 picasso has the 1.6 90 bhp psa engine in it and the mpg averages about 50mpg on mixed driving.
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When talking about these official mpg figures it can be a mistake to just use the combined figure. If you break it down into the urban and extra urban figures, it can soon become clear where the benefit of stop-start systems (for urban figures) and aerodynamics (for extra urban) come into play. When the two figures are combined, the picture is less clear.
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PSA 1.6 diesel engine - wildly differing CO2/econ - -
