Home made water injection

Technical Disscusion Forum will be used for in depth threads that are moved here by a mod/admin member.... everyone is welcome to add their input, but only on topic replys
User avatar
kheading
Regular
Posts: 637
Joined: Sat May 21, 2005 10:12 pm
Location: South Oz

Home made water injection

Post by kheading »

Ok heres what i plan to run but i still have a few holes in tuning it and regulating the flow.

The aplication.

Daihatsu Mira 850cc (+60tho), decompressed pistons and combustion chamber to 8:1, other internal upgrades for reliablity.

Single turbo taken from a 1ggte twin turbo engine (2ltr)

Strait gas before the turbo using a vl throtal body.

Intentions of 15psi, depending on detination and reliabilty upon tuning on the dyno.


Running 8:1 compression, higher octain (lpg) and water injection are my methods of detonation control.

I removed the fuel tank and replaced it with a stainless steel tank to hold the water. A vl high pressure fuel pump then delivers the water to a malpassi rising rate fuel regulator (carby), the regulator provides 7 psi base and increases at a 1:1 ratio as the boost signal rises and excess is returned back to the tank.

Water is then entered to the air stream after the turbo just apon the exit of the compressed air from the turbo, via a vl fuel injector, as they have provisions for the hose to clamp to it.

The water is activated when a pressure switch hits (5psi or less) and turns on the pump and opens the injector.

1 Can the injector function for a long life with a 12v power supply in an on off situation for long periods of time e.g under boost climbing a hill?

2 How do i regulate the flow of water if i have too much of too little. The pressure will increase as the boost does but thats only so it will still deliver the water?

3 Will the vl pump last running water.

4 Will the vl injector perform with 7psi water pressure?




Another thought was to pick up a pulse signal from the distributor, convert it back to a positive signal, to trigger the injector (more detail involed to get this working)but still activated by a set boost pressure.


Thanks Kingsley
Thought it was a good idea at the time to beat-box with shaving cream on my face, until it started snowing.
Gene FJ20DEBT
Supreme Overlord
Posts: 9056
Joined: Sat May 14, 2005 10:32 pm
Location: Brisnyland, QLD AKA: NISMOgemini
Contact:

Post by Gene FJ20DEBT »

sounds like fun.. i know u will get a quick and acurate bunch of answers on performanceforums.com :)
"No thank you, Turkish; I'm sweet enough."

Image
Gemi Coupe
Long Term Member
Posts: 4173
Joined: Mon May 23, 2005 8:33 pm

Post by Gemi Coupe »

post contents removed
Last edited by Gemi Coupe on Tue Oct 26, 2010 9:23 pm, edited 1 time in total.
OGR88 GEMINI
Regular
Posts: 210
Joined: Tue Nov 15, 2005 2:37 pm
Location: caboolture qld

Post by OGR88 GEMINI »

there was a write up on this in street machine have you seen that yet?
Gene FJ20DEBT
Supreme Overlord
Posts: 9056
Joined: Sat May 14, 2005 10:32 pm
Location: Brisnyland, QLD AKA: NISMOgemini
Contact:

Post by Gene FJ20DEBT »

OGR88 GEMINI wrote:there was a write up on this in street machine have you seen that yet?
scan it if posable?
"No thank you, Turkish; I'm sweet enough."

Image
User avatar
kheading
Regular
Posts: 637
Joined: Sat May 21, 2005 10:12 pm
Location: South Oz

Post by kheading »

Gemi Coupe wrote: Another option would to be to use a brass fitting from a sprinkler system and control the flow of water through it via a solenoid and valve. may be a cheaper setup too.
I see what you mean here but i dont understand how to adjust the amount of water as the revs and air stream increases.

I might be able to addjust the regulator i have to give me a higher base pressure.

I like the idea of pulseing the injector like fuel injection. Maybe recive a signal from a set boost pressure to tell a fuel computer to start pulsing and increasing on boost pressure and rpm but thats starting to sound expencive.

Any one know what a fuel only computer will cost?
Thought it was a good idea at the time to beat-box with shaving cream on my face, until it started snowing.
User avatar
kheading
Regular
Posts: 637
Joined: Sat May 21, 2005 10:12 pm
Location: South Oz

Post by kheading »

Thought it was a good idea at the time to beat-box with shaving cream on my face, until it started snowing.
User avatar
kheading
Regular
Posts: 637
Joined: Sat May 21, 2005 10:12 pm
Location: South Oz

Post by kheading »

I assume by having a quick look at it, that i can addjust the pulse rate by rotating the trim pot and activate it when a boost signal is recived, giving the Jaycar board power and can increas the flow by using the rising rate fuel regulator.

Im gonna try the vl fuel pump and see what life i can get from it, i cant see that it should perform any different to fuel in the pump. Fingers crossed.
Thought it was a good idea at the time to beat-box with shaving cream on my face, until it started snowing.
User avatar
Crumz
Moderator
Posts: 1221
Joined: Thu May 26, 2005 2:34 pm
Location: Perthormance

Post by Crumz »

As a side note, the better idea would be to run the pump either all the time, or work out a way to give it a least one second (before required) to prime up.
Turn on any EFI car and you will hear the fuel pump prime the lines to ensure there is something there (with suitable pressure) to actually be injected.

Also, fuel pumps are lubricated by just that, fuel. Water does not work too well as a lubricant on fuel pumps. I don't think KY will work either. Might need to look into a high pressure pond pump or similar? High pressure meaning high for a pond, not 200psi :D :D.
Another Quality Post by Crumz

Fix the roads, not the fines.
User avatar
kheading
Regular
Posts: 637
Joined: Sat May 21, 2005 10:12 pm
Location: South Oz

Post by kheading »

I could run an aditive to the water to help with lubing of the pump but would rather not, as id like to keep it simple once installed.

I was going to have the pump run only once i got the boost signal but the delay could cause problems that im trying to stop. Yes your right, it would be a better system to have the pump running all the time and have pressure there all the time.
There must be a high pressure 12v pump avaliable but at a hight cost i would think.

Would anyone know exactly what internals the vl pump uses, e.g rubber on plastic or steel vanes in plastic tube?
Thought it was a good idea at the time to beat-box with shaving cream on my face, until it started snowing.
User avatar
Frederick Stienheld
Site Admin
Posts: 586
Joined: Sat May 14, 2005 10:22 pm
Location: Brisbane, QLD
Contact:

Post by Frederick Stienheld »

kheading wrote:I assume by having a quick look at it, that i can addjust the pulse rate by rotating the trim pot and activate it when a boost signal is recived, giving the Jaycar board power and can increas the flow by using the rising rate fuel regulator.

Im gonna try the vl fuel pump and see what life i can get from it, i cant see that it should perform any different to fuel in the pump. Fingers crossed.
Surely altering the delivery pressure isnt going to alter the flow from the injector? Wouldnt the injector be designed to work over a range of pressures? To accomodate for fuel pump fluctuations? Isn't the duty cycle the only way to control the supply from an electronic fuel injector?
User avatar
Crumz
Moderator
Posts: 1221
Joined: Thu May 26, 2005 2:34 pm
Location: Perthormance

Post by Crumz »

Frederick Stienheld wrote: Surely altering the delivery pressure isnt going to alter the flow from the injector? Wouldnt the injector be designed to work over a range of pressures? To accomodate for fuel pump fluctuations? Isn't the duty cycle the only way to control the supply from an electronic fuel injector?
In a basic summary, yes. That is the only way to increase the amount one injector will flow.
However, a larger injector will also flow more than a small injector for the same length of open time (duty cycle).
Another Quality Post by Crumz

Fix the roads, not the fines.
User avatar
Crumz
Moderator
Posts: 1221
Joined: Thu May 26, 2005 2:34 pm
Location: Perthormance

Post by Crumz »

Side note merv, is this worth a move to the technical discussion?
Another Quality Post by Crumz

Fix the roads, not the fines.
User avatar
Frederick Stienheld
Site Admin
Posts: 586
Joined: Sat May 14, 2005 10:22 pm
Location: Brisbane, QLD
Contact:

Post by Frederick Stienheld »

Crumz wrote:
Frederick Stienheld wrote: Surely altering the delivery pressure isnt going to alter the flow from the injector? Wouldnt the injector be designed to work over a range of pressures? To accomodate for fuel pump fluctuations? Isn't the duty cycle the only way to control the supply from an electronic fuel injector?
In a basic summary, yes. That is the only way to increase the amount one injector will flow.
However, a larger injector will also flow more than a small injector for the same length of open time (duty cycle).
Yes, the same duty cycle on a larger injector will flow more than on a smaller injector.

But here we have a given injector size (whatever he choses). So, to alter the delivery rate of that injector he would need to alter the duty cyle (via electronic pulses). Increasing the pressure with boost shouldn't increase delivery rate? Instead the pressure just needs to be constant, as it is with the fuel injectors on a normal turbo EFI vehicle.
User avatar
Crumz
Moderator
Posts: 1221
Joined: Thu May 26, 2005 2:34 pm
Location: Perthormance

Post by Crumz »

That is correct. If it's not, then it is in theory. If it's not, then you're wrong.
Another thing that you've got me thinking though, is if this is water injection is going to be used to cool the intake charge, then technically, wouldn't it want to be running full time? You wouldn't want it to only work on 2 cylinders per rotation.
I'm not too sure on water injection and how it's meant to work though, so I could be wrong.
Another Quality Post by Crumz

Fix the roads, not the fines.
Post Reply