Custom made WI with a fail save system (see drawing inside)
 

Hi,

My car is a Volvo V40 2.0T standard 160hp after couple changes hp should be near 180 now.
The car will be custom remapped in May. Water injection is for sharper knock timing and cooling.

I will try to write what I have and how I want it:
Car should be 230hp after custom remap and turbo pressure will be near 1.1bar (16psi) which is pretty high for my turbo and that?s why WI will be needed.
I am planning to build a dual stage water injection, first stage will be activated on 0.7bar (10psi) and second stage will be activated on 1bar (14.5psi), both nozzles will be 75cc/m (1GPH)
Water / Ethanol mixture will be 80% water and 20% Ethanol, I tank 98 octane.

I am going to make a custom build system based on a simple Shurflo pump based system. I made a scheme for electrical and mechanical parts, it is made in Photoshop since I don?t have AutoCAD at home so bare with me if it looks bad.

Here the drawing I made, see below for explanation, every comment is welcome to improve it for a save system:

http://img412.imageshack.us/img412/6...emav4enho9.jpg

Scheme looks complicated but it is actually pretty simple, I will explain what I want after its finished:

• * 2 float sensors in the water tank, one for mid level and it will only activate a LED second one is for low water level, it will directly activate a led inside the car and shut off the pump after certain time, the pump wont run dry since there is still little water in the thank when the low level float sensor is activated.

• * Low level float sensor will also deactivate TCV (Turbo Control Valve) after certain time this way the turbo will run on lower pressure since there is no water system to keep things save.

• * There will be one extra block-off solenoid next to another two (for high and low stage) to prevent water going in to the intake, I have seen couple people having this problem so I decided to go save and use one extra before the other solenoids.

• * To be sure the pressure sensors are on upon turbo pressure, there will be two leds inside the car.

• * A water pressure sensor with a led will show me when there is pressure in the system, same sensor will also deactivate TCV when there is no water pressure while pump runs and a led will be activated to show there is no water pressure.

• * There will be a Shurflo accumulator for keeping nice water pressure.

This is an excellent start.

Would it be possible to add another pressure switch inline (with higher setting) to detect a clogged nozzle?

Thanks Richard,

I already got a adjustable pressure switch for clogged nozzle detection, I was planning for one stage injection that?s why I got one switch, I could get one extra switch and place both switches in each stage after block-off solenoids and before the nozzles for checking clogged nozzles. It is even possible to ad time relays to cut down the turbo pressure if the pressure switch stays on after turbo pressure switches go off.

I read the diagram and did notice the pressure switch you put in. Does this switch do the same job as clogged and no water pressure?

All the rest of your drawing I can understand.

Yes it has normally open an normally closed switch, when there is no pressure it will stay closed (NC) and when it has pressure above the adjusted pressure the other part (NO) will close.

This kind a switch:
http://img374.imageshack.us/img374/5372/switchyw6.jpg

See if I can re-phrase the question.

1) Presence of water pressure - about 30-100psi?
2) When the first nozzle is clogged, about 200psi
3) Only the second nozzle is clogged, about 150psi ?

How does one pressure switch setting detects all three conditions?

If the pressures switch is replaced by a pressure sensor, the above conditions can be isolated incdividually.

Am I making sense?

Ok i saw that coming lol :)

Sure you make perfect sense, but I am using the pressure sensor in the drawing above for detecting the pressure only, so if its set very low you can check if there is a pressure or not.

But I already made changes in my plans I am getting one more pressure switch so I can add 2 pressure sensors just before the nozzles. When the pressure switches are set to 80 psi ? it will show me the clogged nozzle when the pump goes out and block-off solenoids shut the water the pressure sensors light the led longer than the pump led because there is still pressure between the nozzle and de solenoids.

A pressure sensor or a flow gauge would be perfect, but I couldn?t find nice cheap alternative for those, it is my daily driver and the car will be mild tuned, if I could afford a fully save Aquamist system I sure would buy one, since I cant do that I am trying to build a cheaper water injection system with almost all thinkable fail systems in there, sure there will be other things to ad but I think what try to build is pretty fail save especially with cutting off turbo pressure when something fails. Building your own design is fun and educative.

Any suggestions are welcome, so if you see anything which needs to be added let me know please. I like to build something nice made by myself.

I am getting a basic set, not from those guys who use Aquamist?s name ;) and half of their price, and get other things like accumulator and pressure switches plus float switches somewhere else.

I already got myself 2 nice float switches and ordered the accumulator.

This is one of the float switches I got, it came from a Mercedes washer fluid tank and I got 2 different lengths, these are specially designed for cars so it wont jump on and off when water level gets lower:
http://img171.imageshack.us/img171/6...lsensorhn2.jpg

This is the accumulator I am getting, its a Shurflo accumulator:
http://img291.imageshack.us/img291/5...nsievatap3.jpg

I don't have any problem with the rest of the system, well thought out. Just curious how the failsafe works. Now I know that you did not include the clog-jet switch, that is fine. Something you will include soon.

If you are using the float switch, ensure the float will float with methanol. SG=0.79 approximately.

How much are you planning to spend on your system? It appeared you have already invested a great deal of components. They are all good stuff.

I have no objection where you get your part from - I help you to see this through to the end.

I do have one more useful suggestion. Does you pump have a demand switch?

Thank you I really appreciate your help :smile:

I already ordered everything and received couple things, total price is ?470 euro ($617 USD) including shipment costs this also includes one extra 150cc/m nozzle, the second pressure switch for clogged sensors and the time relays (I didn?t order the time relays yet but I know the price). Since I order the parts all over the world the shipment costs where high without shipment it would cost me ?327 euro ($430 USD)

I don?t know if the float sensors will float in 20% methanol mixture but I am pretty sure it will work since they where used in washer tanks and most washers include alcohol.

Yes the pump is an Shurflo 8030 series pump and it has automated pressure switch, and I know what you think, I am going to connect the pump directly so it keeps the pressure in the system with the accumulator, this makes nozzle?s directly spray instead of waiting on the pump building up its pressure. This should be changed on the drawing to but it will require one extra relay to stop the pump when low-level float sensor goes on.

I do have some questions about the nozzle placement, since I use 2 nozzle?s. I will try to show on the IC to TB pipe in below picture with red arrow. I think I will place them with 2cm distance at same spot. This way water would get right to the TB.

http://img151.imageshack.us/img151/2618/nozzlesrt0.jpg

The picture is not from my car I have still a metal pipe waiting to cut like the one on the picture, but I am waiting on the nozzle?s till I cut the pipe.

The accumulator I got is factory pre charged to 20psi, do I need different pressure on the accumulator?

Yes you should increase the bladder pressure --- on my accumulator they had a little data sheet in the box that gives recommendations on the pressure. If I remember correctly the bladder should be pressurized to about the same pressure as the low limit of the expected fluid pressure. I think I charged mine to 85 PSI for a 100 psi system.

If you don't increase the charge pressure the water will squeeze the bladder down so small you will have almost all fluid in the accumulator and no gas in the bladder to help it hold pressure as the fluid is released.

Shurflo may have a data sheet for that accumulator on their web site but I would have to look around for it.

Here is is --- http://www.shurflo.com/pages/Food_Se.../911-378-P.pdf

Larry