DIY - Water Injection

[Snorg]

To put water injection in a fuel injected car you use a jobber windshield washer pump to pump the water, you take the voltage from the throttle position sensor to power the pump, this controls the speed of the pump to regulate the flow. You take a small hypodermic needle the size a diabetic uses the water is pumped through it, then you drill a tiny hole in the plastic of the air intake directly above the throttle body and poke the needle in there. If you need less water use a smaller needle, or bigger one if you need more. You use about 5% water to gasoline. Then you do performance tests to see how much water to use. You don't use too much water or you will start to wash the oil off the cylinder walls. You want almost no water when its idling. You don't want no water when the the engine is cold so you put it on a toggle switch and don't turn it on till the engine is warm. You can use windshield washer fluid in the winter.

[getnpsi]

if a TPS only ranges from 0-5 volts, is 5v enough to make the pump pressure the line to the injector? Do you have to add some sort of throttle position switch? those switches arent cheap, and take away from the whole DIY thing.

[mikemoss]

Originally Posted by RNANS

Hello All
As far as cleaning up carbon deposits and preventing buildup, all you have to do is see a cylinder head of a car that has blown a gasket, allowing the water jacket cooling water into the cylinder...clean as a whistle, ask any mechanic!!!
Water injection itself helps by absorbing the heat in the combustion gases to turn into steam. Everyone knows that water itself has a high latent heat of evaporation...less heat thrown out into the exhaust gases and water jacket means more efficiency. Normally only about 15% of the available energy is used to drive the car, the other 85% or so goes out the exhaust or coolant.
So How does the steam help?
from data derived from WWII aircraft and literature I have read, the steam pressure
(sort of steam engine like) adds to the BMEP (brake mean effective pressure) of the exisisting , burning air fuel charge to force the piston down. The figures I have consistently found are 20-25% of the amount of fuel being used at any given moment. The anti detonant property is already well established. More water than this will not work, ie snuff out the flame front or get mixed in with the oil....one should be well aware of the dangers as someone so rightly pointed out. With regards to WWII aircraft the systems were very simple because unlike cars, these warbirds used their maximum power at a fixed WOT throttle setting in dogfights. In cars there will need to be a proper metering system to realize its full potential, as well as a cutoff during the warming up cycle. If any one would like the references please contact me
The Articles for the voltage controlled DC water pumps are definitely worth a try, but make sure the water is injected downstream of the Hot wire MAF to prevent the platinum wire in the MAF from suffering an untimely death!
Cheers

What you said about the wot steady rpm thing got me thinking. bc 90 percent of my driving is highway cruising at 2000 rpm it would probably be easier for me to make a system that I just turn on when I get on the highway or wire it into the cruise control.

dremd

how did you alter the flow of water with fuel?

Everyone keeps talking about putting the injector before the throttle blade. Would it not work if you put it after the throttle blade? I was just thinking that it would be a lot sturdier in an aluminum intake manifold vs a flexible rubber hose.

The biggest thing I see is that it could cost too much to do. If I can put together a full parts list of stuff I will need and go to the junkyard it could be possible to do it on a low enough budget to make testing worth while though.

[rmay635703]

Not to throw in a tangent but on most newer cars a warm intake improves mileage.

Couple this with water and you have a winning combo.

The way I saw it done was to have a controlled water drip and shroud around the cat area or manifold and duct your intake to suck the steam and warm air in, it gives mileage benefits (which I believe we here would be looking for) without modifing anything electronic related. You do normally get a drop in performance but the mileage gain is fairly consistant as pumping losses get reduced without fooling the O2 sensor.

The main reason to use steam and not water is obvious, it isn't as dangerous if overdone, although it is possible to overheat if your motor leans out too far in the wrong weather.

[getnpsi]

Originally Posted by rmay635703

Not to throw in a tangent but on most newer cars a warm intake improves mileage.

Couple this with water and you have a winning combo.

The way I saw it done was to have a controlled water drip and shroud around the cat area or manifold and duct your intake to suck the steam and warm air in, it gives mileage benefits (which I believe we here would be looking for) without modifing anything electronic related. You do normally get a drop in performance but the mileage gain is fairly consistant as pumping losses get reduced without fooling the O2 sensor.

The main reason to use steam and not water is obvious, it isn't as dangerous if overdone, although it is possible to overheat if your motor leans out too far in the wrong weather.

Steam is a great addition to a carburated application. It's tried and true in the old farm truck community, to keep trucks in service. (you dont work you dont eat.) Modern cars have MAP sensors, and steam...as it's a gas, it will mess with readings, causing the vehicle to hunt around spiking emmisions worse looking to satisfy its preset curves. The best bet for fuel injected cars is to inject atomised mist into the intake plenum. I personally dont like before the TB, pooling can occur if it's a passive system. If it's spraying according to engine load/throttle percentage, then it really doesnt matter the location.

I have a performace water/meth kit in my dodge neon srt-4. Works great. It comes on at 5psi and sprays a really fine mist into my intake pipe after my TB. It was also $250 dollars. I figure i only need 1/3 the pressure and 1/10 the fancy stuff to make a naturally aspiriated car benefit. I dont think a window washer pump will live a long time put to moving that much fluid at such a higher pressure. they are only designed to get a windshield wet once in a while, not held on continuous up a steep grade or towing, or unnatural lean burn etc. Find a good 40ish psi 12v pump, a relay, vacuum switches couple nozzles for testing and youre in business.

[Dust]

Originally Posted by mikemoss

What you said about the wot steady rpm thing got me thinking. bc 90 percent of my driving is highway cruising at 2000 rpm it would probably be easier for me to make a system that I just turn on when I get on the highway or wire it into the cruise control.

dremd

how did you alter the flow of water with fuel?

Everyone keeps talking about putting the injector before the throttle blade. Would it not work if you put it after the throttle blade? I was just thinking that it would be a lot sturdier in an aluminum intake manifold vs a flexible rubber hose.

The biggest thing I see is that it could cost too much to do. If I can put together a full parts list of stuff I will need and go to the junkyard it could be possible to do it on a low enough budget to make testing worth while though.

After the throttle plate means tat you have to fight vacuum. Before means that you don't. After the throttle plate works, but you just have to have it plumbed right, and make sure that you have a way to stopit from sucking water at idle

[Cobb]

Stormin-norman, sorry to hear of your situation you are in with the transition and all between the living and such. Did you manage to go through with this and any results? I am tempted to try this on my insight as it has the i-Dsi ignition and runs a 10.8 to 1 compression and seems sensitive as is to gas quality used. So far he likes BP. I am experitmenting with a non mtbe octane booster and it seems to give the car more balls and less use of vtec to get around.