i noticed differences that u get better mpg using 87 but more power using 89. while using 87 i made to 22 mpg highway hand calculated. i switched to 89, i get 18 mpg on highway. throttle respond was much different between them.

 

your engine retards itself when using low octane,

i dont know about you but i dont want to retard my car

 

i am 17 years old and my father took it for work and he put 87. i always put 89 but it was addicdent.