Nozzle sizing
 

Running 95 octane with BNR's @ 18-19 psi with 50/50 meth to H20 pre throttle body, after turbo (420-440 rwhp) with a 250 psi pump what nozzle sizes should I be using????

I also believe I should run the fast acting AIT sensor pre-spray? The alky kit dealer says no you want the AIT sensor after spray...

At the 200# -ish pressure level, I would suggest an M4 or M5 (post IC) which will put you in the 350cc to 450cc a minute range; a good starting point.

I agree with the AIT downstream--however, I would not spray directly on it. If the AIT is in the elbow, putting the injector nozzle at or near the exit of the IC seems to work well (in my own experience).

"I agree with the AIT downstream--however, I would not spray directly on it. If the AIT is in the elbow, putting the injector nozzle at or near the exit of the IC seems to work well"

Agreed, it didn't really matter for me, I've tried all setups, just don't have the ait sensor close after the spray.

But I chose to keep the fraits at the fmic outlet to keep it from heat soaking in the elbow where I also had it before, and I can use post IC WI mounted just after the fraits, or pre turbo if you have a boost activated switch for the WI.

The reason I ask about the AIT sensor placement is I believe Howard is a proponent of pre spray placement so if you have a water inj. system failure it doesn't lead to engine failure?

I think it's six of one vs. a half dozen of the other. If you place the sensor pre-spray, it will not see the cooling effect that will take place, especially if there's a significant amount of alcohol in the mix. It may be that this is offset by the meth being injected (as added fuel). Certainly, the water will afford you the slightly leaner mixture (AFR) that may result.