Quote Originally Posted by loco_corolla View Post
Another source of information was the BP are the only fuel company which has a true 98 octane percentage in their fuels and that the others all require additives to reach their 98 octane which could explain for the variance in fuel octane ratings found in other fuels.
Not really true. Petrol consists not only of 1 component. It's a cocktail of many different chemicals, some to clean your engine, others to increase octane. And I can bet you that BP also adds aromatics and benzene to increase the octane rating to 98.