I tried mine with 89 & 93 octane... 
to tell u the truth...I don't see any big difference... 
But some oil company  said ur engine will be cleaner if u use higher octane gas. 
Personally, I think 89 octane is good enough... 
Just found this fm my honda's owner's manual 
"Unleaded gasoline, pump octane # 86 or higher". 
Y pay extra for premium gas?? |