Funny, most Jeeps spend their lives trying to avoid sucking up water, but I spent my entire time owning an RX-7 trying to find a way to justify the cost of a water injection kit.
Irony, it is the sucks.
Irony, it is the sucks.
Enjoy, I take no credit for the material posted. Although, I did do a 15second google search and came up with this for more information. http://www.autospeed.com/A_107970/cms/article.htmlRambo1965 said:Water Vapor Injection has actually been around for quite a while. Even these days you can purchase complete systems, but they are very pricey. The idea is simple enough. If you add Water Vapor to the intake manifold, the water vapor will lower the temperature or the fuel/air charge. Once in the combustion chamber, the water vapor will increase the pressure and even help clean out deposits, which will also increase overall performance.
I didn't feel like spending the $300 - $600 for a professional system that may or may not work. My first prototype used a couple of Planters Peanut jars and some spare vacuum tubing I had laying around. For my second prototype, I used a Medical Vacuum Canister ($10) and an aquarium valve, tubing and air stone ($5). This set up worked, but I wasn't thrilled with the low airflow, and the alcohol I was playing with deteriorated the glue I was using on the connectors and even the medical vacuum canister started coming apart. I needed something a bit more sturdy, so I went to Lowes and bought everything I needed for around $25. I bought a half gallon glass jar with a metal lid. I splurged for a brass metering valve, tees and plastic tubing used for ice maker water lines. I even sealed all holes to the jar with JB Weld for resistance to any chemicals I may choose to throw in there. The Safety Reservoir was made using PVC tubing with caps. I then fabricated some metal clamps to hold both tanks together and I suspend them from the metal rod that runs down each side of the engine compartment of my Jeep.
OK. Here is a diagram of how the Water Vapor Injection System works.
The diagram reads from Right to Left, simply because that's how I built it in my Jeep.
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The system has TWO holding tanks. The first is the Main Tank. This is where the water is stored and where the vapor is created. The second smaller tank is the Safety Reservoir.
Air enters the Vapor Injection System through a metering valve. The metering valve is important in order to adjust the amount of bubbles in the water. Too many bubbles will cause too much water to be sucked into the Safety Reservoir. Should you expect to be in rough terrain, you can also choose to close the metering valve, shutting off the Water Vapor System entirely.
After the metering valve, the air travels to the bottom of the Main Tank. I run a T at the bottom of the Main Tank with plastic tubing with holes drilled every ¼ inch. This allows a healthy amount of bubbles to form.
Once the bubbles rise from the water and make some vapor, there is a hole at the top of the tank to move the vapor into the safety reservoir.
Why have a Safety Reservoir, you might ask? Well, should the water in the Main Tank rise up (which can easily happen in a hard corner or on a bumpy trail) and be sucked into the engine. That would be a bad thing. In order to prevent siphoning, the Safety Reservoir will stop siphoning from taking place and allow a place for water to be collected instead of getting to the engine.
There is also a drain in the bottom of the Safety Reservoir. Vapor does accumulate so you will need to drain it regularly.
From the Safety Reservoir, the vapor travels directly into the engine via any unused Vacuum Port beneath the CARB or TBI. Should no port be available, you can splice in to an existing vacuum line by use of a T fitting. It is absolutely critical that the vacuum port be below the CARB or TBI. If it is placed anywhere else, there will not be enough vacuum to make the system work. If there are no bubbles, the system is not working.
I did experiment with adding alcohol to the Main Tank. I used Rubbing Alcohol and Isopropyl Alcohol. I really wanted to try out some Methanol, but couldn't find any. The Alcohol did provide me a noticeable increase in performance, but definitely made some noxious exhaust. I also tended to romp down on the gas a bit more, so that nullified the MPG gains I was hoping for.
Pictures:
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Results:
I drive a 1990 Jeep Wrangler with a 258 motor. A few years ago, I switched to the Howell Fuel Injection System and averaged 14.5 MPG. After installing the Water Vapor Injection System, my MPG rose to a low of 16.5 MPG and a high of 18.1 MPG. I've had it in for 8 months now and can state that it does work for me. I live in Las Vegas and had to remove the system for the annual smog check. While the system was off, my gas mileage once again dropped to 14.5 MPG and rose once I returned the system to my Jeep. Perhaps it's not scientific, but it works for me. During the winter months, I do add some alcohol to the main tank to prevent freezing. With no moving parts there really isn't anything to break. I just have to keep the water filled. During the winter months, I had to fill the tank every month or so. I figure with the blistering heat of summer, I may need to fill it more often.
I was worried that the computer controlling the Howell system might interpret the Water System as a Vacuum Leak. That has not been the case at all. So long as the water covers the bubblers, there is no vacuum leak at all. It's pretty sweet.
I was also very concerned thinking the computer might interpret that the system might be read as a vacuum leak and try to compensate. That simply did not happen. So long as the water level is above the bubblers, the computer does not register any loss of vacuum. My idle is smooth, and I have no noticeable loss of vacuum.it would seem that you are creating a vacuum leak . wouldn't it be better to inject water into the system without adding air. say use an atomiser and a pump .
The glass jar kind of worried me too. But I wanted something I could see through, and glass was the most economical and obtainable choice. Since I suspend the glass jar from the bar in the engine compartment, the glass jar swings freely and only bumps up against the brake master cylinder. I can easily pad it or lock it down if it becomes troublesome.My concern would be about using a glass jar as I am sure it would be banged around when wheeling. I would think there needs to be something more durable out there that could be used.
Back when I was running a parts store I saw an old man with a water set up on on old POS and he swore by it and I thought he was crazy, now I am considering it, who's crazy now. :laugh:
As for injecting the water directly, well that's what those really expensive water injection systems do. I was not trying to avoid the high cost of that by designing a simpler system. It might not function as efficiently as the direct injection method, but it works well enough for me.it would seem that you are creating a vacuum leak . wouldn't it be better to inject water into the system without adding air. say use an atomiser and a pump .
I was thinking the same thing. That small amount of water can't make much, if any difference.You say that one jar of water lasts a month, say, 1,000 miles? There must not be much water going into the engine. As support of this, there is a tiny inlet tube going thru a metering valve - tiny, tiny air flow is occuring compared to the CFM of air flowing thru your throttle body.
So what is really happening here? A very tiny (seemingly minuscule) amount of water vapor is increasing mileage 3 mpg or more? I wonder how this could be. And, again, if it were this simple, why don't the automakers do it: they have billions of dollars on the line to meet CAFE requirements.
If that tiny volume of water vapor would have that profound an effect, then why would one not experience the same increase in mileage in a humid day, or when driving in the rain? (Maybe you never see high humidity in your area.)
I would really like to understand. Perhaps a Hawthorne effect?
Excellent idea. I honestly hadn't even thought of that. Seems simple enough to add in though.Suggest that you add a filter to the air inlet. You are sucking dirty air into your motor. Even though it gets 'washed', small particles of grit will get sucked right in to your motor. You can probably use a small in-line fuel filter, or a motorcycle crankcase breather.
Since I do live in Las Vegas, humid days are simply never an option. So I personally do not know if a humid environment will increase MPGs at all. I wasn't really trying to sell this idea to anyone. I was merely posting what I did and what seems to be working for me. I remembered the whole water vapor injection from the 80's and decided to run an experiment on my current Jeep to see if it would work for me now. It did, and I am pleased with the results. I do agree that the minute amount of water vapor shouldn't increase my MPG's the way it does, but it does. And with gas being so expensive, I am not arguing with the results.You say that one jar of water lasts a month, say, 1,000 miles? There must not be much water going into the engine. As support of this, there is a tiny inlet tube going thru a metering valve - tiny, tiny air flow is occuring compared to the CFM of air flowing thru your throttle body.
So what is really happening here? A very tiny (seemingly minuscule) amount of water vapor is increasing mileage 3 mpg or more? I wonder how this could be. And, again, if it were this simple, why don't the automakers do it: they have billions of dollars on the line to meet CAFE requirements.
If that tiny volume of water vapor would have that profound an effect, then why would one not experience the same increase in mileage in a humid day, or when driving in the rain? (Maybe you never see high humidity in your area.)
I would really like to understand. Perhaps a Hawthorne effect?