Ignition timing : Water Only Vs 50/50 Water/Meth

[parmas]

I have a Toyota 1.5L 300bhp turbo engine and presently I have a tune with just straight water using the 315cc nozzle only just for intercooling.

Now I intend to use a 50/50 Mix for octane increase purposes.

In genereal do I need to increase or decrease the ignition timing when switching from straight water to 50/50 mix ?

Please discuss...

[Richard L]

It will normally be neutral but will need to increase the the injection rate by ~50% or you may loose some incylinder cooling effect but gain on the octane. Increase the rate, you will get both.

[parmas]

It will normally be neutral but will need to increase the the injection rate by ~50% or you may loose some incylinder cooling effect but gain on the octane. Increase the rate, you will get both.

How can it be neutral ?

Injecting methanol is like running racing 110 octane fuel and 110 octane fuel needs advance to produce power..

[Richard L]

It will only be regarded as neutral due to the small amount you are injecting. water and methanol have different effect on knock limits. Water does it by suppressing peak temperature spikes whereas methanol raise the knock limit of the fuel. The difference would be the toll on the ignition system. Both methods require advancing the ignition to be effective.