This Italian car website shows the fuel consumption of various cars at top speed.

I thought you might find this interesting from an Italian car magazine - fuel consumption at top speed. If you wish to look at other models, go to www.alvolante.it, click on "prove" and scroll down.
Alfa Mito 1.4 Turbo: 12mpg. Audi 2.0 TDI 143ps: 10mpg. Volkswagen Golf GTI 200ps: 10mpg. Toyota Yaris 1.33 VVTI: 17mpg. Mercedes-Benz 250 CDI Blue Efficiency: 15mpg.

Asked on 8 April 2012 by KR, via email

Answered by Honest John
That's interesting. Thank you. Helps to get the message across that giving it some beans gobbles fuel, even in small-engined cars. However, because the maximum speeds of these cars varies so much, a better comparison would have been fuel economy at 90mph in a variety of different cars. Then they might have seen cars like the Jaguar XJL 3.0 V6 diesel beating cars like the Yaris 1.33.
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