Originally Posted by Rollo
We've already been through this discussion before. Increasing the octane rating if your petrol doesn't necessarily increase the mileage or the power out of the engine. Yes cars do have octane sensors in them, but unless you have a higher compression engine, then for 90% of cars an increase in octane rating does bugger all difference.
Personally I'm more likely to trust the oil companies or the car manufacturers than a rumour which I've read on the internet. Unless someone can provide proof of this from a reputable source, I'm calling bull**** and shenanigans on this theory.