Low octane, High octane

[boost_guy]

What is the purpose of the low octane and high octane maps in the Evo ecu? Does the ecu just switch to the low octane map when it detects knock? Or does it use the low octane map if the ecu detects knock over a long period of time?

[Freon]

Most likely, if there is too much knock it eventually kicks down to the low octane map. I think on Subarus it kicks on if IAM is below some particular level.

[boost_guy]

I need to know at what point it will switch to the low octane map. Thanks

[Nozay33]

There is a 1D map : "Fuel Map Knock Switch Threshold" that defines when to switch to low octane map...depending on IAM value.

For Euro STI (AH992-5513), this value is set to 4.

[S54fan]

Note that this thread is about the Evo not the Subaru.

[Nozay33]

Note that this thread is about the Evo not the Subaru.

sorry about that...I didn't pay enough attention