dexter

found this on ebay http://cgi.ebay.com/ebaymotors/ws/eB...r4_PcN__Stores
and thought it looks like a decent deal, once i get my urd mods i really want a water injection kit but the urd just seems wayy to overpriced. if i got said one above i would do like trdoldman (believe thats his names) custom 1 gallon tank

anyone have any comments? recomendations?

GTE4runner

That's cool that you are looking at water injection. I am going to build my own setup, and if you are into that sort of thing it's not too hard to do. As for suppliers, I ran across this one a while back but I don't have any experience with them link Keep us posted with what you end up doing and how you like it.

midiwall

Ummm.. be careful.

The picture in the auction is of their dual stage kit, but the text of the auction says it's a single stage. If it's really a single stage, then they sell a "Deluxe Single Stage" kit on their site for $239; the "Basic Single Stage" kit is "on sale" for $145. "oops".


Past that.... There are a number of questions to ask:

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I'll admit that it looks interesting and seems doable. Just ask a couple of questions and be careful with them.



I've sent him a couple of questions:

I'll let you know what I find out.

midiwall

Okay, wow... I'm impressed. I just got a response and it's 12:45 *AM* MY TIME! 3:45am HIS time! (he's in GA)

I've been wandering their forum on the website, and I have to say, the guy (his name seems to be "David") is really on the ball. He's pretty on top of people's questions.

Hmmm...


I just fired off a bunch more babble to him. I'll post up what I find out.

midiwall

Update update...

I've been flipping email with him in practically real time. It seems that he gets paged when he gets an email. So he quite possibly woke up to answer my questions. Incredible.

He gets my vote - and he'd get my money too.

midiwall

Okay, I'm obviously wired tonight, but I have one more update...

There're are a couple of pieces in the URD/Aquamist kit that aren't in the Coolmist kit.

- "FIA2" ("Fuel Injection Amplifier"). According to the Aquamist site, this box will:- A blocked injector detector. Again, from the Aquamist site:The Aquamist site is here:
http://www.aquamist.co.uk/cp/806-009/806-009.html


Now, the Coolmist system has an option to detect a clogged jet, and as for the FIA2 - I dunno that it's doing a whole lot. It's cool to know that the injectors are running at a long duty cycle (80% is considered the resonable max), but for most of us running S/C's, then we're already dealing with that by installing the 7th injector, or larger 305cc injectors in the stock positions.

TRDOLMAN

In addition to what Mark has found out, there are a few more differences. The pump they are using is a Shurflow brand pump. I use those pumps in my work and I have a pretty high failure rate with them. I buy them because they are cheap. They have a tendency to leak. I have to clean the brushes and armatures often. I have two sitting on the bench now that have the pressure switches stuck closed.
The main part that is exclusive with Aquamist is the high speed valve. The high speed valve is cycled by fuel injector signals from the ECU and works very similar to a fuel injector. The other system only has a solenoid that is either on or off signalled only by the pressure switch.
The Aquamist 2D system that URD sells has the magnetic race version pump.
The Aquamist is the very best water injection system you can buy.

I have invested over 7 thousand dollars in performance mods to my engine and I would rather not risk unnecessary damage to it by using a lesser quality injection system. Gentlemen----you get what you pay for.

Dave

FilthyRich

The research and develpnet that URD has done, can be trusted. I for one am not willing to trust my engine to someone I don't know. Gadget has never steered me wrong. He will keep getting my $$$...

MTL_4runner

I figured Gadget would have done his homework on this.
I was thinking there must be some reason why he chose aquamist over even making his own kit.
Thanks for the enlightenment on this Dave.

Gadget

It is easy to put together a cheap water injection system. Cheap is not always better although I know that initial cost is very important. Aquamist has killed sales with their huge price increase, but, once you understand what sets Aquamist apart from the rest you can see why their systems are more expensive.

To increase performance with water injection you have to get the right amount injected at the right time. Not enough and you have waisted your money. To much, you can cause damage and kill power.

Most of these cheap systems are simple on or off systems. When they switch on, they spray a fixed amount of water all the time regaurdless of true needs. You can usually adjust them so that at some point in the whole RPM range and throttle setting, you have the right amount of water, but at all other times it will be wrong. Either not enough or WAY to much killing power. Kind of like a stopped watch is right twice a day, but way wrong the rest of the time.

Think of water injection to be the same as fuel injection. If you take the TRD approach with a single big ass injector and just turn it on and not control the amount of fuel being flowed at all, you will either get not enough fuel, or way to much fuel. Either way, most of the time you are getting the wrong amount of fuel. Now if you find a way to control the amount of fuel given RPM, throttle possition and load, you can get the fuel just right all the time and really make great power ALL of the time. That is what we do with our AIC units that we sell to take over the TRD 7th injector. The right amount at the right time is a great benifit. Our customers that have installed our AIC units on their existing 7th injector systems have seen this for themselves first hand. The wrong amount most of the time leaves a lot to be desired.

The exact same thing applies to water injection. You have to control the amount of water so you get the right amount all the time instead of the wrong amount most of the time. There is an Aquamist system that simply switches on like the cheaper systems and it is called the 1s. We do not sell those.

The 2d system takes a very simplistic approach to make the water injector proportional so the amount of water injected is constantly adjusted so you don't get to much or not enough, it stays completely proportional to the fuel flowing into the engine. We know that the sweet spot for water injection is roughly 9-20% of the fuel being injected. As you mash the throttle more or the load goes up as well as boost, the fuel demands go up. The 2d system automatically alters the water flow to match what the fuel injection system is doing. It does this by using a valve that is just like a fuel injector, it pulses on and off when one of the fuel injectors pulses, and it also stay open the same amount of time the fuel injector does. That is how it stays proportional to the fuel being flowed. The way you adjust the amount of water in relation to fuel is by changing the nozzel sizes. The 2d system is a very simple system and it is very easy to setup and it is truely 3 dementional is the way it injects water.

Now if you want to take it a step further, you can add our AIC unit to the 2d system. We already have it setup to drive the Aquamist high speed valve and you can map the water using a true 3 demonsional map just like a fuel injection map. You can add more water in a specific place, take some out in another, what ever you need to make it perfect for your needs. Using our 3d controller is cheaper then purchasing the one from Aquamist. Don't tell Aquamist, but ours is much better....

OK, so I am sure you can see the value of using a 3d or proportional water injection system over some cheaper on or off system, at least I hope so.

There are other cheaper water injection systems that do alter the amount of water flowed in crude ways. The most typical is to alter the pump speed increasing it as boost pressure goes up and injecting more water. This is very cude. For example, on a positive displacement supercharger you can make full boost at very low engine speeds like right off of idle. You don't need a lot of water then. Just look at how much fuel is being used. If you injected the fuel the same way it would flood the engine. To much water at lower RPMs can induce knock and really kill power. Then as RPM builds and the engine is using more fuel and should be making more power, the amount of water injected has not changed because the boost pressure has not changed. So, in our application, this is no better then a simple on or off system.

Now some others attempt to vary the amount of water injected by using the signal from the MAF sensor. This seems like a good approach at first. More air entering the engine, the more fuel being injected so basing the amount of water being injected based off of the MAF signal makes sense, right? So far so good. We have looked closely at a couple of systems using this approach because I think it has potential. When we reach out to shops that install these types of systems to inquire about reliability and the true end result we hear horror stories about reliability, system failures, pump failures, repeated warranty replacements to the point the installers are not making any money because they are swapping in replacement systems without charge and so on. Makes us a tad nervous about getting behind something like that.

We use and sell Aquamist because at this time it remains the finest, most touble free water injection system that really works. Now don't think for a second that we are blindly locked into being only Aquamist. If we find something that works well, a good value, and above all reliable, we will offer that system as well. We never stop looking and testing. For example we did see a couple of prototype systems as SEMA and we have kept in touch with these companies and told them what I want the systems to do and how. These companies have listened to us and we are waiting to see what they come up with.

So, there you have my thoughts on water injection and why URD is doing what we are doing.

Gadget

dexter

thanks guys

GTE4runner

Thats some good and accurate info Gadget. I have heard that the optimal flow rate of water tends to be closer to 13%, but of course it depends upon many factors and varies with things like injector location, ambient temp, injector spray pattern, etc.

I like the idea of the tuning capabilities that you mentioned, but here's what I was thinking about. This hinges upon being able to use a fuel injector to inject water, and I have not looked into that yet. Water molecules are substantially smaller than fuel molecules so that may be an issue. But here is the idea: Adding a 7th injector with equal flow characteristics to the six providing fuel give 16.7% water to fuel as long as the injectors are matched (flow tested). Run this setup with the input to the 7th injector being identical to the input to the six running the fuel, except that the seventh will only kick on when a user set boost level is achieved. This is what I had in mind, and I don't think the circuitry would be very involved. As I said, the only catch with this setup is that the flow rate of the injector with the water would have to be tested compared to the ones with fuel, but actually I suppose that the water pressure to the water injector could be varied to acheive the desired flow rate. This will not of course provide the tunability that you mention you have available, but I suppose I could have one kick on at 2psi providing say, 10% and then another that kicks on only when the boost is above 10 psi providing an additional 5% or something. And all of that could be tuned.

I'll have to look around on your site to see what you have to offer, and thanks for any input.

Gadget

What you have described is pretty much an Aqumist 2d system. You can try to reinvent the wheel and go through all the associated trial and error associated with it, or just install a well proven system made by a company that regaurded as the leader in automotive water injection systems.

We have sold a lot of these kits and have had very few problems. One guy had two high speed valves and a pump go bad. It turned out that it was due to the stuff he was running through it. Since we got him using the right stuff, all has been well. We also had another guy with a pump that failed and that was quickley replaced under warranty and that has been it as far as problems go.

Gadget

GTE4runner

Hmm it's not reiventing when you make it better Thanks for the info.

Gadget

I think you will find that normal fuel injectors are not compatable with water.

Gadget

GTE4runner

Thanks for being so helpful and courteous