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Questions about water injection...

so i have decided that water injection is something i definitely need to get, mainly since i don't want to buy race gas, but i think it will really help safegaurd the motor when i start turning up the boost. i found this site:

http://www.coolingmist.com/Pagedisplay.aspx?key=waterkits&page=1

their kits look pretty nice and they aren't too expensive, but i was wondering which one to get? my goal is 300 whp on either 91 or 93 octance gas, i have an evo3 big 16g, and i am getting 660 cc injectors, 2g maf, and a keydiver/s-afc for tuning. do i just need a 'singe stage' WI kit or something better? once again, any opinions or comments are welcome...thanks!
 

cheekychimp

Well-known member
Joined
Apr 19, 2004
Messages
7,333
Location
East Sussex, U.K.
Jeff,
First of all, given you fairly modest power goals, I'm not sure you really need WI. That said if your local pump gas is low octane rated, you don't think your current injectors are flowing enough or you just want some of the additional benefits of running WI, I don't really think you need to get too complicated here.

I don't want to get into a major discussion of whether various kits on the market are overpriced, value for money or whatever. This is something you really need to decide for yourself. When you buy a kit, you buy convenience because everything you need comes in the box and saves you the trouble of going here, thee and everywhere to get all the components.

However all things said and done, a WI setup in it's crudest form is composed of a reservoir, a nozzle, a pump, hoses and a means of activation (boost/pressure switch). You can get the majority of this stuff dirt cheap.

After that refinement comes by way of inline check valves to stop water dripping into the intake off boost, low water level float switches to tell you when you are running low on water etc. About the only thing I would say you should really buy top quality for is Nozzles and aquamist are generally considered the best.

My advice?

Get a Shurflo pump. If you aren't going for a top end system with fault diagnostics (what Ken Inn calls the 'anal' setup) the Shurflo pumps are pretty much the best. Run forever, won't burnout if run dry and have enough pressure to pump water all the way from a trunk mounted reservoir if required.

Get some aquamist nozzles (but you'll need a special tap to fit them !!!)

Pick up a big windsceen washer bottle reservoir and bracket from a junkyard.

Get a simple pressure switch that activates around the 8-13lbs mark.

Put the nozzle about 2 inches before the elbow leading into the throttle body to allow atomization before water is drawn into the cylinders.

Finally a word of warning. Tuned correctly, the WI should allow use of higher boost on low octane gas and/or the ability to run a leaner mixture without detonation. If your WI stops running for whatever reason ... clogged jets, reservoir runs dry, hose pops off ... you will be running LEAN which could be catastrophic.

So 'consider' putting some failsafes into the system to detect any possible problems or install gauges and be aware of the warning signs they give such as higher EGTs.

Paul

Speak to Ken Inn as well ... probably one of the most experienced WI users on here. I talk a lot of theory ... Ken speaks from experience !!!
 

cool, thanks for all the info... yeah the highest octane gas i can get is 93, and there is only one gas station like 20 miles away that sells it, so it's not really convenient. i would like to use 91 octane and run 22-23 psi. you don't think water injection would help out?
 

cheekychimp

Well-known member
Joined
Apr 19, 2004
Messages
7,333
Location
East Sussex, U.K.
Quite possibly. Best thing to do is to get a tank of 91 run the car and log it and start SLOWLY turning up the boost. If you do start getting knock then ease off on the boost and fit the WI system. Then tune and log and see how much more boost you can get by compensating with the amount of water you inject. Just remember to get a switch that opens at around 8-13lbs. Open up too early and it can bog ... too late and you lose the benefits !!!

Paul
 

Quote:
my goal is 300 whp on either 91 or 93 octance gas, i have an evo3 big 16g, and i am getting 660 cc injectors, 2g maf, and a keydiver/s-afc for tuning.



Jeff,
I don't know if we've met, but I'm currently doing a lot of what you're talking about. The first question is "do you mean 300whp corrected or uncorrected"? If corrected numbers (what the dyno places like MAC usually report) are sufficient, then I'm already doing what you want to do, with the parts you are talking about using, and didn't need water injection to do it. It's just a matter of the right tuning, and decent breathing through the system.

On the other hand, if you're looking for 300whp uncorrected, that's close to the maximum that the EVO3 16g is going to support at our elevation. That will make it difficult to do on pump gas, because you'll be heating the air a lot. Water injection might really help for that...I've only been able to get into that range on race gas so far. I've been tempted to try the pre-turbo WI as discussed on the aquamist forum in order to get more air through the compressor.

At any rate, I recommend you stick with Amoco 91, even though you do see other fuels rated at 93 sometimes here. I'd also recommend you get your keydiver chip with the double map width option and Kyle's maps. He'll know what I'm talking about, and those maps are much more pump-gas friendly than the stock maps, mostly on the timing side. FWIW, my current combo on a full weight GVR4 has done a best pump gas time of 12.9@105 at Bandimere.
 

yeah i was hoping for maybe like 280-290 whp uncorrected. i am eventually getting cams and some porting done. i don't think i've met you before, but that's cool you're doing the same setup. i just think that the evo3 big 16g is a good turbo, and instead of getting something huge that doesn't spool til like 4500 rpm, i am going with higher compression and like 21-22 psi on the big 16g. i'm more interested in driveability than massive top-end power. there was some local guy who had a scca pro rally vr-4, and he made 382 whp with the evo3 16g. not sure if that was corrected or not (probably was at this altitude), but that is plenty fast for me. and you running a 12.9 is a good example of what i want out of my car. is aquamist the only company that makes a decent kit? did you see that link in my first post? their stuff looks pretty good, and they have a 90 day warranty. anyways, thanks for the reply!
 

There is another 'company' on ebay that sells the exact same kit as the one in your link for the same price and throw in a solenoid to avoid sucking in water. I don't see any of them on ebay now, but it might be worth to wait for it.

Aquamist nozzles could be made to fit whatever kit you decide to go with.
 

Quote:
yeah i was hoping for maybe like 280-290 whp uncorrected.



Like I said, that's a lot of uncorrected horsepower to
get out of an E16g on pump gas at our elevation. It
may be possible, but it'll be difficult. My prediction
is that it's possible on the unit at MAC, but not on
the more conservative Dyno Dynamics unit at Logic or
Super Rupair. I think water injection probably will
be required.

Quote:

i am eventually getting cams and some porting done.




I'm running Crower Stage 1s and an extrude honed intake.

Quote:

there was some local guy who had a scca pro rally vr-4, and he made 382 whp with the evo3 16g. not sure if that was corrected or not (probably was at this altitude), but that is plenty fast for me.




I'd say that had to be an SAE corrected number.

Quote:

is aquamist the only company that makes a decent kit?



They seem to be the only place that makes nozzles everyone trusts to properly atomize the water, especially if running water injection pre-compressor. Lots of people run pumps and everything else from other makers, though.
 

ken inn

Well-known member
Joined
Feb 23, 2001
Messages
7,529
Location
krum texas
with the shur flo pump, you dont need a solenoid if the nozzle is before the t/bdy. and there are mixxed thoughts about putting the nozzle before the compressor. if you put it before the compressor, all you need is a windshield washer pump. i had one like that on my bmw, it sprayed into the carb, which was upstream of the compressor. but, in those days, that needed to be done, because there wasnt any nozzles that could give out a fine mist spray.
 

ken,

a lot of blown/turbo'd stangs run the anderson ford 'mr freeze' setup. its a vacuum system that sucks in air before the turbo, supposedly the turbo/s/c should mist it and depending on boost(vacuum on the intake side) it adjusts amount of water.

do you have any experience with setups like this ? It's dirt cheap compared to aquamist, or even the other ones. the stang guys swear by it.

Mark
 

If you run pre-compressor and don't atomize well enough, the droplets will erode your compressor blades. That's why people run high pressure and aquamist nozzles if they run pre-turbo. If it weren't for that it would be easy to use boost pressure to force the water in pre-turbo.
 

ken inn

Well-known member
Joined
Feb 23, 2001
Messages
7,529
Location
krum texas
anything is cheaper than aquamist. my present system is less than 130.00. but, it probably cost me double that to find out. like, i got a shurflo pump on sale for 38 bucks. the original one cost me 92 delivered. then, i spent 20 bucks for the aquamist tap, now a us source has them for 7 bucks. hobbs switch is 30 bucks from napa, once you do ALL their homework for them, and give them the part number. i probably got another hundred in nozzles, you just dont know till you try them. i always seem to go out on limbs where others either dont go, or are not telling.
 
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