|
Modern cars will mostly be ok running 85 at sea level because they can retard the timing to protect the engine. My Acura might actually become damaged over time if it isn't able to retard the timing enough to prevent knock. The manual states that the engine is designed for 91 octane, and that 87 is the minimum to prevent engine damage.
In OR, we have 87, 89, and 92. BTW, mid grades are always a blend of regular and premium (ever see a fuel truck with 3 tanks?). 89 is 60% regular and 40% premium. Anyhow, I mostly run 87 in my Acura, but lately have been alternating filling up at mid-tank with 87 and 92 to average out somewhere around what it's designed for.
I can "feel" the difference in normal driving between regular and premium in my Acura. This difference is confirmed in more advanced timing on premium, and less advanced timing on regular.
|