Water/Alcohol Injection

"How-to" Page

I originally began this project to help someone with an early Chrysler T1 who did not want to go through the trouble of intercooling. The goals were to supress detonation at high boost (15-18psi), on pump gas, while spending as little money as possible. For details of how water injection does this, read the page that brought you here. This system is not soley designed as a means to increase fuel flow. At one time, I intended to offer this system in kit form. However, in keeping with the "budget" nature of this project, I can not use some of the better components that my customers expect. By providing this how-to page, I intend to clearly illustrate how you can duplicate this system yourself. Note that you may upgrade the components as you budget allows, to increase the durability of the system, but the "budget" model works just fine.

The nozzle: Most people that I spoke to who have made there own water injector have used a small orifice that "squirts" the water into the mouth of the turbo. They rely on the turbo to completely atomize the water. The problem with this is that it is highly abusive to the compressor blades. Eventually, it will errode the leading edge of the blade, just like a sandblaster. If you are using this system primarily as a means to increase fuel, rather than for cooling, you may need to resort to the squirt method to get enough fuel. Multiple misting nozzles could achieve a higher flow, but the complexity would be prohibitive. I used a misting nozzle from McMaster-Carr (www.mcmaster.com) to atomize the water prior to the turbo and avoid this problem. Of course, you need a pretty high flow nozzle to equal the volume of the "squirt" method. I used part # 3178K87, which is nickle plated and has it's own filter screen. By atomizing the water prior to injecting, so far there has been no visible wear. You will need to monut the nozzle in an elbow with a hose nipple on the other side, to allow for the fluid input. I had to search the bins at the local hardware stores until I found some elbows that would clear the nozzle's screen. Cost: about $3 for the elbow, about $5 for the misting nozzle, and about $6 for ten hose nipples (Mc Master #5346K11), you will use the nozzles elsewhere on this system.

The pump: In keeping with the budget nature of the project, I explored several low cost pumps and found that a basic"Roberk" brand(P50), replacement washer pump supplied the required of water pressure that I needed. I've been informed that the Trico brand Part # 11-603 is the same pump. The "dead-head" pressure of these pumps approached 40psi, but it drops as the flow increases. To inject after the turbo (or post-intercooler), you could use an electric fuel pump to attain higher pressures. You may have to use a smaller mister nozzle if you decide to go this route. Cost: about $13, available at "Builders Square", but it may take you 3 hours to get through their damn line..

The tank: Some water injection systems use a pressurized tank (pressurized by boost) for the water supply. Because I intended to use alcohol at some point, I didn't like the idea of a constantly pressurized plastic tank, and the metal ones were too expensive for my friend. So, I decided to use the factory washer tank. This way, I did not have to purchase an additional tank, and there was no problem finding a suitable location. As it turns out, the water/alcohol mix does a very good job of cleaning glass, so the tank still performs it's original function. An added benefit was that the factory "low washer fluid" light could be used to show when the fluid ran low. You will have to drill and tap a hole for a 1/8" pipe thread. This is where you screw in the fitting for the new fluid to pump supply. You will need an 1/8" pipe thread tap w/drill bit and a hose barb fitting. Mc Master #5346K11. Cost: about $6 for a pack of 10.

The siphon block: Why is this section in Red? Because if you screw up here, you can hydrolock the engine. If you mount the discharge nozzle lower than the water source, the water will siphon through the hose and the tank will empty into the turbo the first time you use the system. This is easy to prevent by using a siphon block. However, it is best to mount the nozzle at the highest point in the intake system that you can find. On Chrysler turbos, this is in the hose exiting the airbox. This will minimize, BUT MAY NOT PREVENT, siphoning. If, after "blipping" the system(turning it on/off for a couple seconds), the fluid does not drain back from the nozzle you need a siphon block. Do this test with the engine idling, as the vacuum in the intake may affect the siphoning action. For a siphon block, I used an aquarium check valve mounted to a vacuum tee. Tip the tee on it's side and mount the check valve to one end. You should be able to blow in the free end of the check valve, but if you blow from the other end, it should feel blocked. Attach the output of the pump to one of the free nipples, and the hose leading to the nozzle on the other one. When the system is activated, the tubes will fill with fluid. When it is deactivated, the tube to the nozzle should drain itself, and not refill until the system is reactivated. In other words, when the pump shuts off, no more water flows out of the tank. If the water continues to flow out, elevate the siphon block. My Daytona used this system with the water going into a turbo mounted filter. Since the nozzle position is much lower then normal, this should be a worst case example for siphoning. With the siphon block mounted at the base of the windshield, I have had no problems. If siphoning continues to be a problem, or you want an extra margin of safety, you can use a solenoid valve to block the flow. Just wire it into the output side of your pressure switch. You can use the boost control solenoid from a post 84 T1 application. Since mine is no longer being used (see Boost Control Valve) I used mine to test this method. It worked fine. However, I don't supply one in the kit, since it's usually not needed. Cost: $3, for the check valve.

The filter: It should go without saying that you should only use pure alcohol with DISTILLED water. You can buy the water at the grocery store, but make sure it's DISTILLED, not plain drinking water. Also, wash out the tank before you begin. Having done that, you can add a small filter to the line if you prefer. Since the nozzle I use has a small screen on it, I have not found a filter to be necessary. Just check it for blockage periodically, and before going to the track. For an extra margin of safety, add a small, see through, gas filter in the line.

The fittings and tubing: For the water outlet on the tank I used McMaster #5346K11, which is a 3/16" hose barb with 1/8" male pipe thread on the other end. The tubing is clear,3/16" I.D. ,alcohol resistant plastic, safe to 60psi. Use clear tubing, so you can be sure your siphon block is working. To accomodate the connection to the misting nozzle, I had to use a brass elbow to provide clearance for the screen. Unfortunately, I bought this at the hardware store, so I don't have a part number. You will have to bring the nozzle with you to the store and check the fit.

The activation switch: For initial testing purposes, I used a pushbutton switch mounted on my shifter to activate the system. This way, I could activate the system manually to easily compare before and after results. Unless you are using this sytem as an external intercooler sprayer, you will probably want to use the following Hobbs normally open pressure switch: Part number 76575 (NAPA#701-1575), which you can get at NAPA auto parts. This switch triggers at 5psi, but you can set it higher by using a bleed. The switch cost $25 and the bleed about $2. This makes it cheaper than an adjustable switch by about $8 (hey, it's a "budget" system).

The fuse: I strongly suggest you use one. Put it in line, between the battery and the switch. A 10A fuse should cover most pumps, but if you have a really big one (pump that is), you may need a bigger fuse.

The water/alcohol mix: Many people use methanol for the alcohol portion of their fluid, but I have found a few drawbacks. First, methonal is highly toxic and a known carcinogen. Second, it can be hard to come by. Third, it's highly corrosive. So, I decided to use denatured alcohol which is available at the local hardware store ($7 a gallon). Denatured alcohol is ethanol with a little methanol added so you can't drink it. Although it's still toxic, it's far less poisonous than straight methanol. You'll probably just go blind if you drink it, but maybe you won't die. Ethanol, by the way, is just good old booze in it's purest form. But again, don't drink denatured alcohol. For the water portion, use only distilled water. You don't want to clog the misting nozzle. You can adjust the mixture percentage as you see fit, but I recommend at least 20% water to get some of it's cleaning and in-cylinder cooling benefits.

Installation Instructions: Click HERE

Hose Schematic: Click HERE

Wiring Schematic: Click HERE

Results: Using this system, I have measured nearly a 90 degree drop in charge temperature at 14psi. This was somewhat unexpected. Realize that since the water vapor occupies some of the space normally occupied by air, the power gain is not comparable to what a 90 degree drop with an intercooler provides. But I am happy with the results. I am also able to run 15psi with 15 degrees advanced timing. The friend that I built the prototype system for, is running 16psi without a problem.These measurements were made on a 90+ degree day. Power delivery feels smoother and my plugs show no signs of detonation.