Last year, BMW and Vauxhall tuners and race car preparers Thorney Motorsport undertook a fuel test comparing different makes of forecourt fuel in three different cars – a BMW M3 CSL, Astra VXR and a Toyota MR2. Each car was filled repeatedly with the different fuels over an 8 month period and run on the firm’s rolling road to see what the differences were.
The results appeared on Pistonheads, with Tesco 99 coming out on top, offering up to 40bhp more when compared to 95 octane fuel.
This year Thorney has continued the test but with only one car – the same CSL – over a much longer distance: 11,500 miles in fact, of which approximately 5,000 of those were on Tesco 99 Octane, 4,000 on Shell V Power and 2,500 on BP 102.
Thorney reports that once again Tesco 99 slightly outperformed Shell V Power – which showed little difference from the Optimax of last year – and showed more consistency in its results as well.
As for BP102, it initially gave more power than either of the other two fuels, but the power output dropped off quite quickly with extended running and/or high engine bay temperatures.
Fuel choice remains, as ever, a complex and potentially key subject.
For the full report from Thorney, click here