OCTANE

Don't do it, unless you have either bumped compression ratio, Advanced the hell out of the timing, or supercharged it, you are just waisting money. Plus odds are that the power output will be lower.

With today's computer controls, there MAY be a power increase. The ECU will sense any knocking before we can hear it and will retard the timing to prevent it. That's not saying that premium will be better than midgrade, but I do notice a power and MPG improvement with midgrade (89) over regular (87), especially on hot days with the AC running.

For older vehicles where the ECU only controls mixture, ya... run the cheapest grade that doesn't ping.

--- Rich