Anyone running Water/Alky Injection?

Cool schematic. Looks pretty straightforward. Could you answer an ignorant question though: what is a Hobbs switch?
Mike R.

 

hobbs switch = adjustable pressure switch. switch is close until X psi of boost then it opens, wa la!

 

Most water and/or alchohol injection setups use a fixed pressure pump. This means the motor gets the same amout of water at 14 psi as it does at 25. This can bog the motor just as it's coming into boost. Aquamist and SMC http://www.smcenterprises.com/injector_kit.htm sell variable pressure options. Last year Mike Licht of GM-MAF translator fame was saying that he was working with SMC and would come out with a DSM specific version with the variable rate option. Haven't heard anything about it since.

 

blah blah

... this is the same theory stuff that pushes solenoids, accumulators etc. A basic system works well and you don't *need* a variable pressure pump to make it run great without bogging. Just set the system to turn on once you need it, not 2psi, and you'll have no bogging issues. Of course you can always spend more money if you want to but it's not necessary. My WI works better than I asked for on the street. At the track I turn it off and run race gas.

 

[curtis]

Chris what size nozzle are you spraying with. I have already figured out how to do everything on mine its just the amount per/min I'm wondering about.

Edit I saw you said .8 but with your pump how much does it accually flow in real life. I don't want to hydrolock the engine of screw some sh*t up. Also what does the nozzle look like is it just a hole or a oval or is it like a small micron screen inside. Also I was thinking of spraying it at around 8 psi.

 

It flow "enough", as I've never measured it exactly. I'm sure it flows some what more than the 285cc/min estimated by the aquamist chart at 7 bar since my pressure is higher. I bought a .6mm and tried that first. Went up to a .8mm with no issues. I could go bigger or add multiple nozzles but it's surpressing knock and I get zero bogging so i'm happy without playing around anymore. You won't hydrolock your engine unless you're a complete idiot which I doubt any of you are. It's spraying a fine fine mist at any significant pressure. Hook everything up but putting the nozzle in the piping and turn the system on. You'll like the mist you see and be amazed at the flow.

I chose the big pump because I figure the pump has 20psi swings when "cycling" and it's seeing 20psi in my piping. So I'm seeing pressure of at least 110psi minimum I'm guessing. But a 100 psi pump is just fine, just don't get the 60.

Edit: You're shooting for 20-25% water to fuel ratio (remember injectors x 4 @ *100%* DC is your fuel flow). So you have to fudge around a bit as I'm not really at full capacity of the 660s *most* of the time. Plus the psycrometric chart isn't fun for most to read so no one does. It's all a big range anyway, you're shooting for knock supression not exact flows. Still get knock? up the jet size. Getting bogging? Raise the start pressure or go down a jet size. But .6-.8mm is probably a good range for most people who actually *need* the knock supression on pump gas.

 

[a_santos]

I am also planning on getting water injection in the future. Here is what I was thinking I would like to do. Is it possible to hook up two hobes switches, and run 2 nozzles. One a small nozzle, .6 or smaller, and another nozzle, maybe the same zise or larger. One hobes switch for each nozzle, but one of the nozzles only comes on at full boost, while the other comes on at early boost, lets say 6psi. That way you would not have any bogging issues, but would have enough water to cool the charge and suppress knock. I also think that the amount of water would be better matched to the airflow.

Sort of like having two banks of injectors.

What do you guys think? Will it work?

 

It will work fine but you'll have to have a solenoid to have them come on at 2 different pressures. Just try a setup like I've drawn out for you. You can always add another nozzle later but I bet you will find you don't need it. KISS.

 

[14bCrazy]

quote:i use methanol(denatured alcohol) in the winter to stop freezing in the line. I thought that I read on the Aqua Mist site that you shouldn't use Denatured. I use real Meth. that I get from my local VP dealer. It cheap hell I think for a 55 gallon drum it's less than $150.00.

 

[14bCrazy]

quote:8. How do I prevent the water from freezing in winter?
Use a 20% Methanol/water mixture or use "windscreen additives" that contains Methanol (wood alcohol) or Iso-propanol (rubbing alcohol), check it before purchase. Methanol is better than other forms of alcohol and is totally compatible with Aquamist products. Avoid using Ethanol based additives such as De-natured alcohol or Methylated spirit.

I toke this from the Aqua mist site.

 

[ken inn]

i dont use the aquamist pump, the shur flo is fine with denatured, and i only use about 10%. i think the water in the blue stuff is NOT distilled, so it clogged up my filter completly. the aquamist pump is 300+bucks, and they do fail. also, whomever designed the mounting for the pump is an idiot, or a brit, same thing. my shurflo cost me 72 bucks DELIVERED. and, i can get them in a day. but, i have never needed another. accumulators, solenoids, whatever, are not needed. i ran a .6 and a .7 together for years, now only the .6, and i cant tell the difference. when i first installed it, i had it spraying right when it went into boost, and the motor bogged just a tad. the dsm's can take a whole bunch more water. i am ordering a much larger nozzle. oh, and that tap is really wierd. no one is stupid enough to have a tap in that size.

 

Lots of good info here. I'm glad I started this thread.

For $72 I might just go with a Shure-Flo 100psi unit. Where do you get them from?

I am going to try the nozzles from Mc Master since they seem to be working for a few other poeple I have spoken with and they have a simple 1/8"NPT thread so no issues there. I will be sure to let everyone know what size works best.

I really need to get this done when I am done freshening my motor since I got my PDA back today and immeciately went out and logged and am getting around 24-28 counts of knock on 16psi. Even turning it down to 13 only decreased the knock down to 16-20 knock counts. The O2s were staying constant so it wasn't going lean. Might be a bit lean to start, but it wasn't going lean per say.

 

mcmaster carr nozzles have to go in from the opposite side. Get the aquamist ones. you won't be sorry you spent the money.

 

Chris you need a little stick figure guy with thought balloons on your drawing.

I never looked into water injection, so from an idiots standpoint, what would be the total dollar amount you'd end up spending on a system like this?

 

i think you can do it under $200 if you get the 100 psi pump. Definitely not more than $300. Crap for $300 I will build them for people with the 100 psi pump and your choice of nozzle.

 

Here is a pic of the McMaster nozzle in a TB elbo.

I might try both and see if there is any difference..

 

[iceman69510]

This is like being back in school!

Professor Water Injection, can I use regular gas and get better mileage cheaper too?

 

hehe good catch Jeff. I actually ordered the wrong hobbs switch the first time since they do come in NO and NC varieties! Ooops. The part number posted should be the right one though.

 

[Hertz]

quote:Originally posted by keydiver:
I now am using the Aquamist highspeed solenoid, and have developed an injector driver for it, so it will inject more water as your injector pulsewidth rises. When you do this, you also need to raise your jet sizes, so I have another 7mm to replace the 4mm. Now, if I only had the time to install and test the driver circuit.

Now that is genious. Industrial-age mods just don't excite me anymore, we need more technology! Let me know if you need a guinnea pig.

 

quote:Originally posted by keydiver:
quote:Originally posted by Pivvay:
hobbs switch = adjustable pressure switch. switch is close until X psi of boost then it opens, wa la!

Actually, the Hobbs switch works just the opposite: it is OPEN until X boost, and the contacts close, activating the pump or solenoid once you hit the appropriate boost pressure you have dialed in. The Aquamist switch does work the other way.
I'm running the Shurflo 100psi pump, with a 7mm and a 4mm jet. I now am using the Aquamist highspeed solenoid, and have developed an injector driver for it, so it will inject more water as your injector pulsewidth rises. When you do this, you also need to raise your jet sizes, so I have another 7mm to replace the 4mm. Now, if I only had the time to install and test the driver circuit.

What's the frequency and current draw on the Aquamist solenoid?

I've got a bunch of LM1942 drivers laying around in a box somewhere. They're not as nice as the NLA Cherry drivers (they need more external parts), but still pretty beefy. I can try and dig one or two and mail 'em to you if you want, Jeff.