nismo.capri Posted February 12, 2007 Share Posted February 12, 2007 A quick run down on water injection The idea of water injection goes way back however it wasn't used in production engines untill WW2 IIRC. There are 2 reasons for using water injection 1) Detonation Supression 2) Adding power through the expansion of steam. Water injection put on to a well running engine wont do anything except keep the combustion chamber clean. Water injection when setup properly will allow an increase of ignition timing or the use of lower octane fuels because it slows the speed of the flame front in the combustion chamber. The other way water injection can make power is to turn the engine in to a hybrid petrol/steam engine. Add enough water to the air/fuel mix and when it turns to steam it will push on the piston same as the air/fuel mix does. For turbo engines WI can act as an intercooler. The reason for this is that turning water to steam or just heating water takes heat which it gets from the compressed intake charge. People have found that if they are having a detonation/pinking/dieseling problem even when the timing is correct and running the correct octane gas that it's due to carbon build up. To fix this they steam clean the combustion chamber while on the car. Here's the method. 1) Get the engine hot (don't do this with a cold engine). 2) Wind the idle up to about 2000 rpms or get a helper to contol the gas. 3) Get the garden hose and starting with a trickle aim it down the carb throat. 4) Slowly increase the flow of water untill the engine stumbles a little then back it off a bit. 5) do this for 5 mins or so. You should see a lot of white steam out the exhaust. 6) Take if for a drive after to get rid of any excess water vapour in the crank case, probably best to do this just before an oil change. !!! Warning !!! If the engine should stop take the spark plugs out and crank it over. You don't want to hydrolic your engine. This is an old trick that dates back to the ex WW2 aircraft mechanics that got in to hot rodding. They noticed that the water injected aircraft engines were spotless in the combustion chamber and when they had a car engine that kept detonating they'd give it the steam treatment. There are 2 different theories, carbon has built up so much that it has effectivly increased the CR and/or the carbon is causing hot spots that are pre igniting the fuel. RON NOVAK'S DO-IT-YOURSELF WATER INJECTION SYSTEM http://blizzard.rwic.und.edu/~nordlie/w ... 14-01.html Links and some testing on Water injection http://blizzard.rwic.und.edu/~nordlie/water_injection/ For the hardcore geeks here's the chemistry From: Robert Harris To: DIY_EFI@lists.diy-efi.org Subject: Water and its effect on combustion. Date: Mon, 10 Jul 2000 10:24:08 -0700 Message-ID: <9ptjms0uu4oe292mpk6a6vhm2hn8bu9h1j@4ax.com> Let us take a quick look at ignition. Those who have a Heywood can look it up - mines on loan so going by memory. The first thing that happens is a plasma cloud is formed by the arc consisting of super heated electron stripped atoms. When this cloud "explodes" a ball of high energy particles is shot outward. The highest energy particles are the hydrogen atoms - and they penetrate the charge about 5 times as far as the rest of the particles. As they lose energy and return to normal temps - about 5000 k - they begin to react chemically with any surrounding fuel and oxygen particles. The effectiveness of spark ignition is directly related to the availability of free hydrogen. Molecules containing tightly bound hydrogen such as methanol, nitromethane, and methane are far more difficult to ignite than those with less bonds. During combustion - water - H2O ( present and formed ) is extremely active in the oxidation of the hydrocarbon. The predominate reaction is the following: OH + H ==> H2O H2O + O ==> H2O2 H2O2 ==> OH + OH Loop to top and repeat. The OH radical is the most effective at stripping hydrogen from the HC molecule in most ranges of combustion temperature. Another predominate process is the HOO radical. It is more active at lower temperatures and is competitive with the H2O2 at higher temps. OO + H ==> HOO HOO + H ==> H2O2 H2O2 ==> OH + OH This mechanism is very active at both stripping hydrogen from the HC and for getting O2 into usable combustion reactions. Next consider the combustion of CO. Virtually no C ==> CO2. Its a two step process. C+O ==> CO. CO virtually drops out of early mid combustion as the O H reactions are significantly faster and effectively compete for the available oxygen. Then consider that pure CO and pure O2 burns very slowly if at all. Virtually the only mechanism to complete the oxidization ( Glassman - Combustion Third Edition ) of CO ==> CO2 is the "water method". CO + OH ==> CO2 + H H + OH ==> H20 H2O + O ==> H2O2 H2O2 ==> OH + OH goto to top and repeat. This simple reaction accounts for 99% + of the conversion of CO to CO2. It is important in that fully two thirds of the energy of carbon combustion is released in the CO ==> CO2 process and that this process occurs slow and late in the combustion of the fuel. Excess water can and does speed this conversion - by actively entering into the conversion process thru the above mechanism. The peak flame temperature is determined by three factors alone - the energy present and released, the total atomic mass, and the atomic ratio - commonly called CHON for Carbon, Hydrogen, Oxygen, and Nitrogen. The chemical reactions in combustion leading to peak temperature are supremely indifferent to pressure. The temperatures and rates of normal IC combustion are sufficient to cause most of the fuel and water present to be dissociated and enter into the flame. As can be seen above, water is most definitily not only not inert but is a very active and important player in the combustion of hydrocarbon fuel. Ricardo and others have documented that under certain conditions ( normally supercharged ) water can replace fuel up to about 50% and develop the same power output, or that the power output can be increased by up to 50% addition of water. This conditions were investigated by NACA and others for piston aircraft engines. It is important to note that these improvements came at the upper end of the power range where sufficient fuel and air was available to have an excess of energy that could not be converted to usable pressure in a timely manner. As a side note - Volvo recently released some SAE papers documenting the use of cooled EGR to both reduce detonation and return to a stoic mixture under boost in the 15 psi range - while maintaining approximately the same power output. Notice - they reduced fuel and still get the same power output. When you consider that EGR consists primarily of nitrogen, CO2, and water ( to the tune of about two gallons formed from each gallon of water burned ), you might draw the conclusion that it also was not "inert". They peaked their tests at about 18% cooled EGR - which would work out to about 36% water injection and got about the same results under similar conditions that the early NACA research got. Quote Link to comment Share on other sites More sharing options...
Ogre Posted February 12, 2007 Share Posted February 12, 2007 i looked intot his a few years ago hardcore.can use 50/50 water methonol mix too. Wouldnt recomend the garden hose thing tho, us a nib off a sprey can or somthing to atomize the water better, dont want "drips" in there.All the same it does work. Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted February 12, 2007 Author Share Posted February 12, 2007 i looked intot his a few years ago hardcore.can use 50/50 water methonol mix too. Oops yeah forgot to mention that. That's why a lot of the yanks use windscreen washer fluid because it already is a 50/50 mix. Wouldnt recomend the garden hose thing tho, The garden hose treatment isn't water injection it's for cleaning out carbon deposits.... sorta related us a nib off a sprey can or somthing to atomize the water better, dont want "drips" in there.All the same it does work. Depends on what the aim of the injection is. If it's to make power via steam expansion injecting a liquid is more efficent. Did you build a system? Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted February 12, 2007 Author Share Posted February 12, 2007 cheap easy WI setup. Attach a tube to the windscreen washer pump, run the tube to the intake. put a spray can nozzle on the end of the tube, mount the nozzle. Obviously this can be inhanced with a seperate switch activated by the throttle. A PWM circuit to adjust the flow rate etc... Quote Link to comment Share on other sites More sharing options...
Ogre Posted February 12, 2007 Share Posted February 12, 2007 nah never ended up making it as i wouldnt have really got anything out of it.Engine wasnt pinging or anything, mite try it on the LA tho, the steam clean thing, i think its pretty fool of carbon.The carbs warn and runs real rich masses of carbon come out when doing keyoffs lol Quote Link to comment Share on other sites More sharing options...
Burntrubber Posted February 13, 2007 Share Posted February 13, 2007 Me an a friend made a setup about three years ago for his 1.5 SOHC turbo 323 think it was an 84. We used a washer bottle pump from a VT Commy because they run 35-40 psi which is good compaired to jap ones. A proper misting jet from aquamist and an adjustable pressure switch to turn it on. We just used washer fluid with a little extra added methonol worked sweet as he ran 12psi for about 4 months then it blew the head gasket and he thrashed the tits off it. Quote Link to comment Share on other sites More sharing options...
pies Posted February 13, 2007 Share Posted February 13, 2007 so im thinking a washer bottle set up but the trigger wire is connected to a micro switch which is set off the the throttle. where am i injecting the water into? if i ran the hose into the air cleaner and straight down the centre of the carb? and am i after a jet or a spray? Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted February 13, 2007 Author Share Posted February 13, 2007 so im thinking a washer bottle set up but the trigger wire is connected to a micro switch which is set off the the throttle. Sweet. for extra geek points use a PWM controller to control the flow. where am i injecting the water into? if i ran the hose into the air cleaner and straight down the centre of the carb? and am i after a jet or a spray? either will do but a spray is better. Start with a spray can nozzle Quote Link to comment Share on other sites More sharing options...
pies Posted February 13, 2007 Share Posted February 13, 2007 so im thinking a washer bottle set up but the trigger wire is connected to a micro switch which is set off the the throttle. Sweet. for extra geek points use a PWM controller to control the flow. where would i aquire such an item? and... spray/jet right down the middle of the carb from the air cleaner? Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted February 13, 2007 Author Share Posted February 13, 2007 where would i aquire such an item? http://www.jaycar.co.nz/productView.asp ... &SUBCATID= and... spray/jet right down the middle of the carb from the air cleaner? Yep, I had a K&N cylinder jobbie and I jammed a pipe through the top of it..... I'll see if I can dig up pics... Quote Link to comment Share on other sites More sharing options...
lowlancer Posted February 13, 2007 Share Posted February 13, 2007 So it's almost like an injector but with water? Like a super fine mist? Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted February 13, 2007 Author Share Posted February 13, 2007 Injectors don't like water sadly as they would be ideal but yes. Yep a mist, atomised not vapourised. As Gary says: Water vapor won't do, liquid water is needed in the cylinders for either cleaning or anti-detonant use. A carb intake does a reasonable job of distributing liquids. Anything poured down the carb while the engine is running will get a shock as it passes the throttle plate. Of course an atomized but not vaporized spray is best, but anything that doesn't hydraulically lock the engine will work more or less. Quote Link to comment Share on other sites More sharing options...
Burntrubber Posted February 13, 2007 Share Posted February 13, 2007 My friend got his misting jet from this place I think he got the switch from there also. http://www.waterinjection.co.nz Quote Link to comment Share on other sites More sharing options...
mk5corty Posted February 13, 2007 Share Posted February 13, 2007 bwahah ill just jam the paint gun full of water into the carb. Quote Link to comment Share on other sites More sharing options...
Spencer Posted February 13, 2007 Share Posted February 13, 2007 so anyone tried this hose down the carb stuff? one of my mark 2's splutters and keeps on going after the keys off but otherwise runs mint. Just abit skeptical of where that carbons going to go? Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted February 14, 2007 Author Share Posted February 14, 2007 so anyone tried this hose down the carb stuff? one of my mark 2's splutters and keeps on going after the keys off but otherwise runs mint. Just abit skeptical of where that carbons going to go? Yep done it a few times. Just keep the revs up and if it dies turn it over with the spark plugs out to clear any water. Quote Link to comment Share on other sites More sharing options...
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