Originally posted by DemonSVT:
Premium has a higher flash point. (slower to ignite)
Normally aspirated vehicles.
The cars requiring premium normally have advanced ignition timing starting the flame front earlier and allowing for a longer burn time.
A car programmed to run regular fuel would still have timing set for regular fuel and not start the flame front as early and therefore lose power and efficiency because the fuel was not achieving maximum burn time.
Simple explanation. Other factors are involved as well.
I respect your opinion (the flash point thing I'm not sure about right now, still checking), but I have to disargee with you on that one. I get better mileage out of the 92/93 octane than I do the 87 in both of my vehicles, and I have no altered computer program/chip in either. For some reason in my tours early life (under 10K), the premium gas I used actually killed 4 O2 sensors. I switched back to 87, no more lost O2 sensors. Now the real funny part is that I went back to 93 octane again and I haven't lost an O2 sensor since November 2000. I have no clue what to make of my car sometimes...
