Slightly OT (only because in Australia we have different octane ratings) but here is a real world test done by running 3 identical vehicles on 3 different fuels - E85, E10 and PULP (98 octane). The vehicle is specified by the manufacturer to run on regular (91 RON), it is the most 'average' car in Australia, but has an engine that can adjust timing and fuel delivery cycles for different fuels - so this shows what happens when you put non-specified fuels in, and how the engine responds in real world conditions.
Ethanol put to the test: E85 v E10 v premium unleaded
You'll have to change your mindset to understand our L/100km measure of economy, and our different octane rating.....and then stop yourself falling off your chair when you see what we pay for fuel. But......overall, if you skip to the summary of the article.....
Even though the car with the cheapest fuel returned the worst economy figures (used most fuel, ran for less kms) it was still the cheapest to run.
But if your main goal is to achieve best performance, fill up less often, and protect your engine (with 'additives') then premium is the best choice for both around town and on the freeway.
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2005 3.0d Sport - Sapphire Black
Engine : Bluefin Superchip Tune,
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