If you are injecting pre-compressor at 2%-3% rate compared to air flow you will have about all the WI you need.
Suppose you spray at 2% air flow rate, and you have a 11.5:1 fuel air ratio at red line.
If you are flowing 65 lb/min, that is 29510 grams of air per min.
At 2% flow that means you would be injecting 590 grams / min of water.
If you have an 11.5:1 air fuel ratio than your fuel is 29510/11.5 = 2566 grams / min
Since most gasoline has a density of about .78 then that is 3289 cc/min
10% water to fuel would be 329 cc/min
15% water to fuel would be 493 cc/min
You would be spraying about 18% per min to fuel if you sprayed 2% of air by weight with a max power AFR of 11.5:1.
The beauty of using the air flow is is self corrects as you lean out the fuel.
the higher your AFR (say 12.5:1) the higher your percentage of water/fuel at a fixed water to air ratio.
Since many engines will report mass air flow directly in grams /sec it is trivial to find 2% of your max air flow in grams per min, which directly converts to water flow in cc/min.
If you delay WI turn on until 10 psi Manifold pressure or so the turbo will be well spooled before the water comes on.
Bottom line:
(a) Will injecting too much water cause it to puddle in the intercooler creating problems? --- possibly but that would quickly evaporate as the intercooler cools down as long as it was not a huge amount of over spray.
(b) Will it be necessary to inject more water post intercooler for knock suppression?
Probably not in my opinion.
On the atomizing nozzles I've looked up they most only need to have about 30 psi air supply pressure to work properly.
Not sure why you would want to run such high pressure unless you tapping a pre-existing high pressure supply.
Larry
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