Lots to comment on Zed_thirteen
Over here in Canada and most of the USA, we have regular 87 ron, Midgrade 89 Ron and Premium 91 Ron. There are a few stations offering 94 Ron as a super premium but it's really hard to find.
European cars like Mercedes Porsche and many of the Japanese Like Acura Lexus require as a minimum, 91 octane. If you put in 87 octane they will run, but like shit. Currently here in Port Perry Ontario, regular (87 octane ) is $1.08 CAD, Midgrade 89 octane is $1.18 CAD and premium 91 octane is $1.28 a lot of Canadians running the European cars are using the midgrade to save 10 cents /liter and I would have to estimate the average Canadian drives 1-1/2 hours round trip to work daily, so gasoline is a fairly big ticket item on the budget. I would guess $80- $100 a week per car and due to cost of things here, most husbands and wives work, so that 150-200 dollars a week at the fuel pump/family.
An interesting test I used to do to show the young bucks why they were wasting their money on 118 octane, was to take a teaspoon of 87 octane gas and spill it on concrete, then drop a match on it. It would go Whoof like a big dog. Then take a teaspoon of their 118 octane gas and do the same test. It would barely light and no Whoof like the cheap gas. So they would stand there mystified and trying to figure out what the hell was going on. That's when I started a rant on high performance engines and why they needed to spend money on increasing compression to get more power and then use the high octane gas to be able to fire the high compression without detonation. At the end of my rant, they would say "Ok , just tell me what to do" rather than try to learn the technical aspects of racing engines.
The following user(s) said Thank You: zed_thirteen, Neville
Our regular unleaded petrol in the UK is either 94 or 95 octane.
Just to avoid (or increase?) confusion: In North America, gasoline is rated by the 'Anti Knock Index" or average of the RON (Research Octane Number) and the MON (Motor Octane Number), i.e. (RON+MON)/2 which is typically lower than posted 'Octane' numbers (for the same fuel) in other parts of the world.