MSefi.com read only forum (Jan.15,2018)

(Mods, feel free to move if this belongs in another forum.)

I'm trying to get boost-pressurized water injection to work but I can't find a mister that will work at 10-15 psi.

Can't find a carburetor jet small enough and greenhouse misters don't work. I just get a fine stream of droplets, not mist.

Am I mistaken in thinking the water needs to be a mist? It seems that a fine stream or droplets wouldn't get along too well with the turbine blades.

Can anyone give me a clue as to what I can use for the mister?

Regardless of which nozzle you use, I believe its agreed that injecting AFTER the turbo is best. Fine mist and small droplets are both harmful to the blades. Earliest, you could inject would be just after the compressor outlet, then maybe again before/after the intercooler.

Also, higher injection pressures will do wonders for atomization. The $60-80 Shurflow pump will push about 50-80 psi, and no need to boost-pressurize anything. Ideally you'd run a regulator to keep constant relative injection pressure, much like the fuel system.

gielamonster wrote:Regardless of which nozzle you use, I believe its agreed that injecting AFTER the turbo is best. Fine mist and small droplets are both harmful to the blades. Earliest, you could inject would be just after the compressor outlet, then maybe again before/after the intercooler.

Also, higher injection pressures will do wonders for atomization. The $60-80 Shurflow pump will push about 50-80 psi, and no need to boost-pressurize anything. Ideally you'd run a regulator to keep constant relative injection pressure, much like the fuel system.

Thank you for your reply!

Unfortunately, I couldn't inject after the turbo with a boost pressurized system. Mounting yet another pump and all the wiring and plumbing necessary for it isn't something I want to do. I love the boost-pressurized system's simplicity but it doesn't look like it's going to work.

There`s been a few instances of the turbo blades pitting even with high pressure pumps and nozzles ( I think people put it down to droplets forming on the sides of the inlet to the turbo?).

As gielamonster says after the turbo is the only safe solution and the only time I`ve seen boost being used in WI is to presurise the water in the resovior to the main pump.

I've been looking for water injection threads, surprised this one is still here, I thought all posts were deleted
after 3 months unless you were a demi-god.

Good info from keithmac, my thunk would be circular grooves in the cone/reducer into the turbo to create
surface turbulence to get any water off the surface and broken up.

My information is that you really do want to inject before the turbo, the droplets absorb heat and make the
turbo much more efficient: http://www.aquamist.co.uk/phpBB2/viewtopic.php?t=267

rgds,
-phil