I've read a bunch, but I haven't heard a lot of downside?

Pros: More power, water is free to supply.
Cons: Weight at the track (Big deal).

Obviously I am missing several things. I am thinking about this, cause I only want a TMIC, but I want to get as much out of it safely as possible for a vf34/18G turbo. Should I consider WI? Please help me.

-Scot

WI is a great alternative to high octane fuel. It has very similar effects, but the water is free. It has also been said that WI cleans the combustion chamber a good deal.

The only drawbacks are the extra complexities of the system, and also having to tune for it. Another issue is that if you do tune a setup with WI to the edge, then if the WI fails for some reason, you will likely cause major damage to the engine.

-- Ed

Pros: Run cooler with more and safer power. You also get better open loop fuel economy since you are not using fuel to cool the cylinders and pistons.

Cons: Accidentally running out of water makes your pistons very unhappy.

Pro: you can pass emmisions tests. The inspector that I had checking my car over thought his sniffer or program wasn't working and couldn't figure out why my particulate counts were so low. I only had 1 cat.

Con: putting the injector before the turbo and chewing your compressor blades up.

For a pretty much stock WRX...

Would it really increase fuel effeciency?

- and -

Would you be able to run a lower octane?

[sounds like it could be an interesting investment with all the increasing gas prices these days...] [and if you could switch between a water injection map and a completely stock map using an Access Port (if you accidentally run out of water) this could be mighty interesting...] :D

[QUOTE]Originally posted by Psydotek
[B]For a pretty much stock WRX...

Would it really increase fuel effeciency?

- and -

Would you be able to run a lower octane?


[QUOTE]

I think you could see mayjor gains even on a stock wrx, but you need some kind of engine managment to tune for the WI.

Yeah you could also tune it for lower octane, I'm considering that myself. But, I doubt I'll do that, I don't mind paying a little more for now. Although I would think you could tune for lower octane with a stock wrx and a utec, but I would see the point. You be loseing power.

Oh and I can't see it really helping the day to day fuel effeciency. But under WOT You'll see gains. You can run leaner a/f ratio's and it you use methenol mix it'll be getting some fuel from that.

bump for a good thread

Originally posted by Vaus
\Another issue is that if you do tune a setup with WI to the edge, then if the WI fails for some reason, you will likely cause major damage to the engine.

-- Ed
This is taken care of with a proper WI setup, correct? I'd never install a WI setup on my car without the failsafe features/monitoring. Cheap WI setup = bad idea.

Join Date: Apr 2003
Location: San Diego, CA
Posts: 1,970 My next project...

--------------------------------------------------------------------------------

http://www.rallycars.com/Cars/WaterInjection.html
http://www.kennedysdynotune.com/waterinjected.htm
http://www.aquamist.co.uk/cp/cp.html

You can read up on what I want to try. First of all, you skeptics. Keep your biased water opinions to yourself. I have been reading up on this for about a month now and have even talked to some Cobra guys and they are using the same setup. They say it is even beneficial to N/A guys but in lesser form. Turbo and Super guys will see the best gains. Research all about this, but you want 10% of fuel supply. Say that I have 4 x 440cc injectors. I want 10% of the total capacity. About 150cc of water injection. Spraying right before the TB. Everything that I have read goes hand in hand with what Hondata did with a 40shot of N2O. The water will vaporize and cool down the IAT thus decreasing CDT. I look at it like this. I won't get the kick of nitrous but I will get the decrease temp and more fuel because of denser air intake. Future may even be a water/N2O setup, who knows.

http://water.lovehorsepower.com/

With the picture and description of parts, you could have this kit for less than $200. The most expensive parts are the pump and accumulator. They are about $100. All the other parts are Home Depot items for about $100.

That was a post from ClubRSX.com. I just cut and pasted. Not starting wars.

And of course turboice.net (http://www.turboice.net/)

I don't think there is a downside to WI, it's a good safeguard. That being said, DON'T use it as a power adder. Run race gas if you want to run race gas like AFRs&timing, don't rely on WI to do so.

Originally posted by dwx
I don't think there is a downside to WI, it's a good safeguard. That being said, DON'T use it as a power adder. Run race gas if you want to run race gas like AFRs&timing, don't rely on WI to do so.

Why not??

If the WI system is set up PROPERLY with the risks in mind, there is no reason not to tune for it. The problem is that a system like this is somewhat hard to create.

-- Ed

Originally posted by Vaus
Why not??

If the WI system is set up PROPERLY with the risks in mind

That's pretty much the point. A lot of people are just throwing around the "properly set up". Besides the Aquamist 2c or 2d kits with the FIA2 aux electronics, very few people have mentioned installing a water pressure gauge or a water level indicator to monitor clogged nozzles or low water level. And if one of these instances occurs, with most of the DIY kits out there all the driver can do is try to stay off boost. The Aquamist FIA2 has the ability to send a signal to your boost controller to operate at a safer preset.

Also the water to fuel ratio is another important factor, too much or too little water can be equally as bad. One reason the dual nozzle setup is popular is because the solenoids open at different pressures, so at low pressure only one nozzle is operating, and at high pressure two nozzles are operating to give a better water/fuel ratio. You can see the large potential problem with a single nozzle system. The Aquamist HSV (vs the on/off solenoid) monitors injector duty cycle and can give very good control over this aspect.

Just some other things to think about that should be included in a proper setup. The UTEC is probably capable of a lot of the things that the Aquamist aux electronics can do, but I've only read detailed information from mr2guru and NavyBlueSubaru about really fine tuning WI.

http://waterinjection.info/phpBB2/

One of the bigger cons that I've read for Water Injection is that it strips the cylinder walls, which promotes premature engine wear.

Of course, I'm still running WI anyway...:D

The cons of water injection are cost and complexity. A WI setup cost you way more than most account for. A decent WI setup costs at least $400 (using aquamist as exa).

You will spend at least 2 days installing everything and double checking your work. Priming pump, hoses, high speed valves, HP pump, nozzles, nozzle driver (FIAA2 for aquamist), switch, failsafes, status LEDs, tapping nozzles, time delay relays, etc. This system is complicated if you want to do it right. I have one rocker switch that swaps maps AND activates the water injection system. I credit Ed (turboICE) from Charged Performance for the system design and install. It turned out pretty slick, albeit complicated.

You also need EM capable of map switching. Only two I know of are Utec and Xede (popular anyways). say $800

Next, is the hidden part....Tuning. You should account $$ for another additional tune on top of your base map. Your tuner will spend just as much (maybe more) time working your WI map and setting up the flows initially. (say $300) for WI tune.


With all this added up, you get to about $700 pure out of pocket expense, plus install time and or $$$. You still need all the complimenting mods too..EM. That is quite a bit of $$$ for roughly %10-15 power increase. But water is basically free, so for those that have it... enjoy that investment.

tdxflex,

I completely agree with you that a trully proper system is much more complicated than people think. I am, however, setting out to put together such a system including my own controller to control a high speed solenoid. http://forums.nasioc.com/forums/showthread.php?s=&threadid=520243

My system will also incorporate a return line with an FPR-like device to keep pressure across the nozzle constant under varying boost.

As far as failsafes, it would be fairly easy to hook up a level switch and cut boost when out of water. The hardest thing to detect is a clogged nozzle. Since my system will have a regulated return line, a clogged nozzle won't show up as a pressure change.

-- Ed

I have the WRXTuner Water Injection kit. I've installed the pump so far and I'm working on making sure I have all the failsafes that I want in place. I put the micro-pressure "water level" gauge in my washer resevoir. I'm using two switches for water power. 1) to turn the power to the pump on, and 2) to control the power to the solenoid. Then the UTEC will provide the switching on the solenoid.

Then I created a circuit so that IF the water level is low, it turns on a blinking red LED. Also, IF the blinking LED is on (ie, low water level) AND the switch for the solenoid is on (ie, I think I'm going to spray water), THEN it turns on a loud piezo buzzer so alert me that I am being stupid.

I also got a VDO pressure gauge that is not labled oil pressure or anything, just that it reads in PSI. It reads 0-150 PSI, and my pump maintains line pressure at 100PSI. I haven't decided if I should put the sender inline before the solenoid, or after.

I'll probably put it before because I can monitor a pump fail situation, when the solenoid is closed, and a nozzle failure situation if the solenoid is open.

Originally posted by wgknestrick

Next, is the hidden part....Tuning. You should account $$ for another additional tune on top of your base map. Your tuner will spend just as much (maybe more) time working your WI map and setting up the flows initially. (say $300) for WI tune.

Second that. listening to friends with WI, they had to pull out a significant amount of fuel to get back to the original power levels they had. Going from ~10.5:1 to ~12:1. That's where fuel economy goes up; using 10% less fuel when running hard.

Tom