[Nezil]

It's actually a bit more complex than that. There is no straight conversion from AKI to RON because the MON value needs to be considered as well.

It is basically true that 91 AKI is roughly equal to 95 RON and 93 AKI is roughly equal to 98 RON, but that's not always the case.

I'm no expert, but my understanding is that MON is actually the more important value for our forced induction engines, and it's totally possible for a fuel to have a really high RON and a really low MON and still equal 91 AKI. This would be a poor quality fuel but would still be 91 AKI. In the rest of the world this poor fuel could be marketed as 97 RON, but it wouldn't be as good as another 97 RON that had a higher, but un-reported MON.

There is also ethanol content to consider. In California, all fuel can be up to 10% Ethanol, without being reported to the customer. This results in all fuel being E10 here. Ethanol has a high AKI rating, so California's 91 AKI is likely around 88 AKI base gasoline, with the Ethanol raising the AKI to 91. In my car, this seems to perform as 88 AKI according to Halim's analysis of my BM3 logs.

Usually if Ethanol is mixed in to your regular pump gas, E85 will be available in your region. Sadly, this fuel can actually range from E70 to E85, usually depending on the season and region (colder seasons in colder regions lower the Ethanol content to help with cold starts). In California, winters aren't cold, so I've heard that our E85 is usually pretty consistent.

Finally, in the US it's usually possible to get various types of Race Gas. It's certainly not as widely available as regular pump gas, but for me at least, there are three Race Gas suppliers in a 20 mile radius, where they sell 100/101 AKI from the pump, and other octane fuels in 5 gallon pails. There is usually both RON and MON data for these fuels.

Doing a poll is a nice idea, but it would need to be a really long list.