Agreed with all previous.
IF you are experiencing knock in your n/a car on 87, try going to 89 (or even 91).
IF you are NOT experiencing knock, the higher octane will do nothing for you.
You are most likely to experience knock under heavy load (flooring it, lugging up a steep hill, pulling a trailer/heavily loaded, etc.).
If you are experiencing significant knock driving normally on a level road, either your fuel rots (is OR fuel as bad as CA fuel? ), something'* broken (vacuum leak, plugged cat, etc.), or your car needs some serious maintenance (e.g., new plugs, de-carbonizing).
P.*., ONLY use unleaded fuel, whatever the octane...leaded will kill your O2 sensors and catalytic converter.
2004 Buick Lesabre Limited, Gran Touring; Bone Stock
1998 Buick Lesabre Limited, Gran Touring; Mods: Poly sway bushings/endlinks, Tru-Cool trans cooler, Thrasher shift kit (med), PLIM, front PEM; Mods in progress: Alot of stuff, but slowly...