Is 3 stage water injection excessive? Thinking of.....

5psi-1gph, 10psi-1gph, 15psi-3gph or

5psi-1gph, 10psi-2gph, 15psi-3gph

I am thinking of running 21psi max and advancing the timing all i can.

 

Probably not but also remember how fast boost climbs so you might be out doing your effort. This is why most kits use a progressive controler becuase it basically does the same thing. If you run a lower pressure through a 5 gph nozzel rated at 100psi and start at 50 psi it is actually 2.5gph starting at 5psi of boost and it ramps up to 5gph by 21 psi of boost. So it does the same thing just much easier and you have less parts that could cause error.

 

i dont know about progressive controllers...........in fuel injection, you keep the fuel pressure constant and pulse the injectors. In progressive controllers, its the opposite, you keep the injector/nozzle open and modulate the DC voltage. To me, its just a disastor waiting to happen especially if you have the tune so aggressive that the car will not be able to run w/o injection!

 

Well I think you need to so some more research becuase the fuel pressure doesn't stay the same with fuel injection. It changes all the time, thats the reason their is vacum(negative air pressure) and boost (positive air pressure). The fuel pressure changes with this. Thats the reason why it is connected to a pressure source off the intake manifold. You pulse injectors more so due to rpm increase along with manifold pressure increase. Since the fuel pressure is higher you can hold the injector open longer with more duty and have a stable amount of fuel.

If you knew anything about tuning you would already know a FI car acts better on more pressure than excessive amounts of ign timing.

Don't post a question asking for opinion then come back to strike the person with incorrect information offering help. I have done alot of tuning both injection kits would work but you can tune better on a progressive type system, end of story.

 

"If you knew anything about tuning you would already know a FI car acts better on more pressure than excessive amounts of ign timing." Care to elaborate on that as I am interested too.

 

Fuel rail pressure increase/decrease wrt to MAP; deltaP=constant

 

FPR pressure doesn't stay constant in fuel injection car so if you raise fuel pressure you can lower duty cycle of your injectors. If you have a fuel injector rated at 560cc at 43 psi it would push more fuel more at 80 psi of fuel pressure.

In most cases the 4g63 have been known to produce more power going for higher boost levels instead of more ign timing. Alot of tuners prefer boost over ignition timing. You don't need excessive amout of ign timing to produce good power on an efficient motor.

I am pretty much done with this thread. Have a good one.

 

Just get an Aquamist FIA2 and HSV. The FIA2 pulses the HSV at the same rate as your injectors so that you have a constant water to fuel ratio. There aren't any progressive controllers that do that. Progressive controllers simply increase the injection as boost increases, but you want to keep increasing injection, based on airflow ( or fuel flow), just like the ECU does with your fuel injectors.

I use this setup in my Eclipse and it works fine. I'm just suggesting that this is the best way to do it, without having to deal with dual-stage, triple-stage, controllers, etc.


Eric

 

In a normally aspirated FI car, the rail pressure stays relatively constant.

In a turbo car, the rail pressure rises with the boost pressure, but the difference in pressure between the rail and the manifold stays constant. In other words, whether the manifold is at 0psi or 30psi, the injector never sees anything different than a constant ~45psi at its nozzle.


But fuel atomization quality suffers because the injector nozzle is designed to be most efficient at ~45psi. This is why injectors come in different sizes but are all standardized to the same pressure.

Ignition advance is no substitute for boost pressure, and this is true for any engine.