So I had some spare time today and and was looking at the spare airboxes I have laying around, so I decided to make my own water mister or water injection setup.
I will be taking pictures and adding details once I get back from Mexico.

At first I drilled a hole in the airbox directly in front of the MAF sensor, this seemed like a ideal spot for the time being as it feed straight in the intake without having to remove anything else. I had a push switch mounted by the steering wheel to manually activate the pump.

One the turbo generated above ~8 psi of boost I would press the switch and have the nozzle spray a small and fine mist of water/alcohol (Windshield washer fluid)

Now, I have a otherwise completely stock car, so I am not able to adjust the timing or change my fuel maps to make use of the cooler charge and increase power. I have no data at the moment but my ghetto experiment seemed to yield smoother and consistent power all up to 12psi. Now the main reason I did this was to clean my engine every once in a while with the power of steam My slight miss at idle is gone.

Any thoughts? I see no drawback whatsoever unless to much water is added to the system, the MAF appears to be unaffected as it's constantly under negative pressure, the engine get steam cleaned from carbon buildup and the overall effects of cooling the air.

 

I'd be concerned about getting the AFM wet.

 

I have spares, but that being said I ran it all day without any issues. I am considering changing the location of the nozzle past the intercooler to avoid possible turbo cavitation and damage to the MAF sensor, or I might ad a nozzle between the turbo and the MAF sensor and run the smallest nozzle to have the a super fine mist.

But back to the MAF issue, I consider it to be unharmed by the mist as the high vacuum is constantly pulling the water. maybe?

 

Are you planning on activating the system by hand/manually?

 

If you are injecting it into the airbox, you are getting your air filter and AFM wet. I would highly recommend you move your injection point to behind the intercooler.

 

I'm not a big fan of water injection before the turbo, but if you are, you need the finest mist you can get and they usually point the nozzle at the center of the compressor wheel.

I know water injection still works on a switch, but its better to use a controller that controls the amount, and when it sprays, then you won't need to always be thinking about pressing a button. I'm sure you can find someone selling one used if your on a budget.

And like people already said,"not in front of the MAF".