Stainless Steel Injectors for Water Injection?

[beerhead]

It may be worth looking at the late model 12 nozzle 50 micron mist injectors I've pulled them from - 3MZ and a 2AZ (I think beams 3S are the same). I bet they help atomisation with fuel injectors and water if they work better on fuel than standard type injectors.

[MWP]

Problem is they rust, hence looking for stainless methanol injectors above.

[TH Performance]

Yes, that is why u need a propee stainless one.

Use aquamist. And have no worries!

[Duk]

The reason for wanting to use a stainless steel fuel injector is quite simple, no potential pressure drop between a solenoid valve that is at a duty cycle that flows less than the spray nozzle can.

It looks like Coolingmist, AEM and probably others are claiming to be able to provide variable water flow by controlling the pump, and I'm sure they can. But how can they vary the pumps output and maintain constant system pressure???
It doesn't seem possible to me to be able to vary pumps output but maintain a constant pressure against an orifice that stays the same.

What happens to the spray pattern/mist 'finess' at lower pressures versus full pressure? Invariably the drop sizes increase with a reduction of pump pressure.

[MWP]

Exactly... and thats why if a suitable injector cannot be found (looking rather unlikely), multiple nozzles and solenoids is the next best idea.
With 3 solenoids/nozzles you could get 8 steps of flow control if you want to get tricky.

[JustenGT8]

Kinda, i think you guys are overcomplicating things. Just for background, the variable rate pumps don't keep a constant line pressure but may try and keep a constant pressure differential across the nozzle (just like the FPR). That aside, even at their lower pressures they should still be running well over 100psi and atomisation isn't an issue.

The other thing to consider is how fast changes are happening....stepped solenoides and even pump control have issues and effectiveness will vary widely simply on where the nozzles are placed. You may be controlling the nozzle/injector well but it's delivering water to what the engine 'was' doing, not 'is' doing. Single point fuel injevtion was shit for a reason

A good mapped WI setup will give the best result but IMHO even a simple pressure switched system sized for fow at peak torque will give 90% the benefit (if not more) and little to no downside. Sure as shit will be a heap cheaper and more reliable as well

Sureflow 120psi pump, switched by ECU (or simple hobb switch even) with a couple of aquamist injectors (multiple smaller nozzles to improve atomisation) and you are away?

[Duk]

I thought I'd add to this thread.
I just today got an FJO solenoid valve water injection nozzle and attached it to my Adaptronic for some testing.
With the engine idling, I drove the solenoid valve add varying duty cycles and at some different frequencies.

A few things I noticed:

A largish drop of water always forms on the little 'scatter point' (the small piece of metal that points directly at the orifice to help break up/scatter that water spray). The actual mist that is sprayed is quite fine, but nothing to get excited about.

The solenoid valve doesn't operate at lower duty cycles with higher frequencies. In other words, to operate at low duty cycles the solenoid valve must work at lower frequencies like 25 and 50Hz. So just setting a base frequency of say 200Hz would limit the usable operating range. Running at lower frequencies causes the valve to be noisy.

At this stage I'm not overly excited by the behavior of the valve, but in its defense I am using an older pump that has the internal pressure switch 'switch the pump off' system rather than the newer/better internal pressure regulator (the pump bleeds off the excess pressure internally, back to the inlet to maintain pressure).