i recently bought a 94 gsr (118k) and without thinking, i have been fueling my vehicle with a cheap gas. octane 87 to be exact. about three weeks in, i realized my mistake, filled the rest of my tank with high test (93) bought some octane boost.. that's where i am right now. since i am new to the vtec world, i have some worries. i pushed my car tonight and when pulling into the driveway, i noticed a strange sort of rattling when accelerating. sounded like loose change. the noise i think started around 3 grand when i was idling, give or take. i'm freaking out. are my worries correct? am i undergoing detonation? what's the noise? please, help a new kid out. thanks.