Ever since my Like turned over 1000 miles I have been running 87 octane in it and it has been running great. I do know they rate the octane differently in different places throughout the world, and our 87 octane is not the same as say China's or Europe's 87 octane. Even in 100+ degree temps, I don't hear any knock or ping, but I do get quality fuel, not from El-Cheapos Gas down the street.