you should only use 89 octane . thats what the vehicles engine is built for. the higher the octane, the higher the compression needed. so if u decide to use 93 octane gas, u are only making your engine work harder than it needs to to get that gasoline to detonate
whatever the owner manual tells you to use. if it requires 89 it will say that. do not use any higher than you have to. google studies done on efficiency and hp with octanes of fuel. the lower the octane the car can run the better performance out of the vehicle (at least this is what was published in an article of sportrider magazine about hp comeptitions for crotch rockets)
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