Originally Posted by mocohead
When you are in EcoPro the car runs a more lean map to get better economy. So your car runs as lean as possible which puts it as close as possible to the limit of detonation.
Creative, but untrue. Eco does not run a different A/F map, it merely changes the foot feed response. All modern cars employ an A/F map which minimizes fuel consumption except at WOT where the map goes rich.
As a separate matter, AKI 89 is fine for the engine under all circumstances. Its use does not place the engine on the verge of self-destruction.
Stand back! He's running 89! It will blow any minute!