Z4 fuel consumption tests

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Zmeagol
Joined: Wed 08 Oct, 2003 15:38
Posts: 1375

  Z4 roadster 3.0i
Location: Putney

Z4 fuel consumption tests

Post by Zmeagol »

On our way to the Swiss Meeting we travelled together as a group consisting of my Z4 3.0i SMG, DavidM's M Roadster, and GaryW's Porsche 996 Turbo Cab. The total distance from Boulogne to Luzern was 570 miles and progress was fast except for hold-ups near Strasbourg. Nevertheless the average speed was a credible 73.2 mph and the Z4 returned 27.1 mpg over the 570 miles. We made fuel stops together and despite travelling at the same speeds, typically I was putting in just under 32 litres of fuel to DavidM's 39 litres, which makes the Z4 about 18% more economic than the M (or to put another way, the M uses 21% more fuel).

On the way back I was travelling alone and to keep me occupied I did some extensive consumption tests. I set the speed against the GPS which is more accurate than the speedo, and maintained it with cruise control. Each run was over more than five miles and repeated several times. I was careful to choose straight sections with practically no hills. The softtop was raised and aircon switched off. The results are as follows:<pre><b> MPH MPG</b>
60 47
70 44
80 37
90 30
100 25</pre>At 80 mph the Z4 is extremely relaxed with revs of just 2,800.

Tim
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