water turn on boost point for base system
 

I don't run race fuel ever[I'd like to but because of cost and lead etc I don't] That's the reason for water injection and now in my area NE USA the highest octane is now 93 down from 94. I plan to now go to staight water instead of water /Methanol just to supress detonation as I feel the amount of octane added and the volume needed to reduce detonation and add power is not there compared to straight water. Please correct me if i am wrong.
My question is when is a good boost point to activate the water injection?
Sometimes I will get a detonation signal from my computer and I notice that if I slam the the throttle open the signal will be indicated BEFORE high boost is reached. Other times if I use the throttle more gradually the detonation signal does not happen. Is it the advance curve,,the boost curve[I'm making a dual stage boost controler but haven't tested it yet}
or is it the forged pistons rattling under low rpm /high boost conditions /OR is it that my water injection comes on at 14 psi and not lower?
Any info would be great,
Sato

My experience with 1s is it'd be better start injecting water at about 50%~60% of full boost, or even sooner. Since the pressure from the pump would not go to the top instantly. Trigger it sooner will let it deal with coming high boost better.

The effect is very obvious especially at the urgent upshift slam as you mentioned.

Or maybe your ignition is too aggressive or lean out or both....

I Thought it might be that
 

I'm hoping that might be it I run about 19 to 23 psi boost and I guess turning it on at 14 to 15 psi might be abit late .I have retarded my advance [thru the computer] and did help somewhat and the fuel ratio is good. On the dyno in 4rth gear at wide open thottle it was ok. No detonation but on the street in lower gears [2nd and 3rd] it would show up. What do you think about using NO alchohol? I'll ry turning the water injection on a 7 to 10 psi and see what happens
Thanks for the input,,,I'll try it.
Thanks,
Sato

Re: water turn on boost point for base system
 

Sometimes I will get a detonation signal from my computer and I notice that if I slam the the throttle open the signal will be indicated
BEFORE high boost is reached. Other times if I use the throttle more gradually the detonation signal does not happen.Detonation will most likely happen when engine is under load.Soon as you shift to a next gear the load goes up then tappers off.

I tried having my WI turn on at around 8 psi and a problems have stopped.
Thanks!