Lets Talk Water Meth Injection

[DaveO74]

I reckon it would be easy enough to install yourself if you know your way around an engine bay.

The general rule seems to be about 80mm from the TB iirc so you should have enough room on a 26.

My 25 has a ff plenum with a very tight radius bend and there is plenty of room.

Edit: just had a brainfart. You don't have a single TB, I'm just guessing but you'd still install it just off of the plenum I spose?????

[TiTAN]

They seemed pretty soft on the tuning side of it. I would have wanted to see jet_r31 type results AKA insane.

Mine should arrive today, ill unbox it Saturday and if I get time will possibly install.

The Snow site recommends an additional solenoid if you are going to boot mount, but the guy from the performance shop I got it at said its just to stop siphoning and not to worry too much unless the nozzle is a lot lower than the bottle (in line). He also said because it will be in the boot and the nozzle at the TB, the hose will probably run through the cabin or under the car, so siphoning wouldn't be an issue.

Can anyone with one of these things installed give me an idea? I was going to get Mick to fab me up a 10L boot mount cell, so it would have a fair amount of gravity pushing down on it.

thats similar to my setup, and i am running the solenoid.

[tridentt150v]

Hmm, but I want a big alloy tank in the back of my car, not a plastic one that doesnt specifically fit where I want it to lol

Alloy and methanol don't mix...........pretty sure I read that somewhere!!! You might be better off with SS?

[The Mafia]

you didnt copy the part where he says he is only injecting water, ofcourse that wont change the AFR at all. you have to have the meth in there to do that.

I was using 275ml \ min nozzles, and the methanol did not change my AFR at all. I eventually tuned my car to 12.8:1 AFR and 20psi on boost on a Standard unopened 100,000km old RB25. I was heading towards 13:1 AFR but decided to sell the motor and start building a RB25\30 to play with.

Car made 320rwkw in the end, 750nm of torque at 3,000rpm in 4th. The rear housing on the GT3037 was only a 0.63. I pushed that f**ker to its limits.

So it is the methanol that increases the octane

You know, I am not 100% sure, but I am almost certain that the water \ steam in the cylinder would act as a retardant in the combustible mix, cooling the fuel and air, causing it to become less combustible (and prone to detonation).

Methanol gets very cold when atomized. it will definitely cool the intake charge before it hits the cylinder. Fuel does this too. (Hence why some people have to run richer mixtures)

Edited March 29, 2012 by The Mafia

[The Mafia]

And for anyone else in the market for a kit, my advice after owning am average system (snow performance), get a REAL kit.

These are real kits:

http://www.aquamist.co.uk/

They have a high speed solenoid that pretty much injects the water like a fuel injector. You simply cannot go wrong with this setup. Its worth the extra $$ to. A kit failure means a possible blown engine at high RPM \ Boost.

[GTScotT]

Interesting. So you think the Snow kit is a toy? LOL Just interested to hear your feedback, having owned one.

And thanks Titan, Ill grab the solenoid when the time comes.

[r33_racer]

Definitely need a stainless or plastic tank if running methanol. It eats raw alloy easily and quickly. If you must use alloy then get it anodised so it can handle the methanol abuse.

I have the cooling mist kit with the digital gauge controller for my twincharge setup. I got 1 injector in the compressor outlet (before supercharger inlet) and 1 injector before the throttle body. I fabbed up a stainless tank for the boot that holds about 20L from memory. However it isnt running yet so I cant report on how good or bad it is.

[GTScotT]

Looks like its a stainless tank then.

Thanks guys,

[DaveO74]

The tank I was talking about

http://www.coolingmist.com/pagedisplay.aspx?pid=Protank1

Turns out it does come as a stand alone unit without the pump

[The Mafia]

Interesting. So you think the Snow kit is a toy? LOL Just interested to hear your feedback, having owned one.

And thanks Titan, Ill grab the solenoid when the time comes.

yeah it is to be honest.

The aquamist is a system fully designed to mimic a fuel injection system.

The Snow performance system had its problems like:

- If the car sat for a while, or you drove it off boost a lot the hose leading up to the nozzle would be empty. So if you came onto boost after driving without spraying for a while you'd get a quick ping when the car is under a lot of load.

- Its a messy kit

- All pressure and flow is controlled by adjusting the pump voltage (Other kits have the pump on full time, and pushing pressure behind a solenoid injector. The solenoid controls the volume of WM going in)

- Plastic tank had a f**king piece of shit lid that fell off and didn't screw on properly. Chinese shit.

- Nozzles deteriorate quicker than you think

- Nozzle "holder" was poor design. Very hard to not get the nozzle jammed in there.

- The plastic bends and fittings go hard, crack and split after a year or two. This stops the kit from working.

- The hose supplied is crap

etc etc

it did work very well, but I decided that for the life of my engine, I would much rather a kit that is more reliable and has better quality parts.

[GTScotT]

LOL I wish I knew that about 2 days earlier. Nah I'm sure it will be fine.

One thing I am now wondering though.. And Titan should be able to clarify.. Does the system purge when your using the optional solenoid? Or still suffers from the same issue?

It cant be that bad really.. Surely the hose would fill up really quick and be fine if your careful with your first few boot fulls. I will go into my experiences when the time comes.

[jarrod83]

Hey Guys I thought I’d chime in with a picture i found ages ago when i was researching wmi, it’s one of those a picture tells a 1000 words...

The only changes in blue yellow and green runs is they changed the ignition timing, which you can see from where the combustion pressure starts to increase. The timing with the water methanol injection turned on is somewhere between the yellow and red runs.

It's clear with the water methanol injection turned on that your peak combustion pressure is reduced, whilst increasing the average combustion pressures and most likely the combustion pressure at the angle where peak torque is made during a combustion cycle.

I also have the hfs-6 aquamist kit, if anyone has any questions, its been a while since i looked at the other kits, so I can’t quite remember all the reasons why i choose it over the other systems. It has a very quick response time, theres no overspray, you can measure flow, detect blockages and overflow, and can send a signal to ecu/ebc when the wmi kit is not working or turned off. I haven’t figured out the best way to set up the failsafe yet.

It detects the duty cycle of your injectors and increases flow linearly with the injector duty cycle. You can also add in a map sensor signal so it can compensate the flow for increased boost.

Im using a AIS 3 gallon tank, it was one of the neatest and tidiest tanks i could find, the wmi pump bolts up underneath it, making the install fairly tidy.

http://www.alcoholinjectionsystems.com/p117/AIS-3-Gallon-Competition-Trunk-Mount-Water-Methanol-Injection-Tank/product_info.html

For anyone who’s interested to know how much wmi they should be injecting, a aquamist site has this link on calculating the jetting:

http://howertonengineering.com/tech-info/calculating-jetting/

Also anyone that’s considering what ratio to run, its usually considered that a 50:50 mix is the best, as its not flammable and you get a better cooling effect on the charge due to Daltons law of partial pressures. Simply you can cool the air down more with a mixture of 50/50 than just using straight water.

Regards

Jarrod

Edited March 29, 2012 by jarrod83

[zoidbergmerc]

my housemate had WMI on his R33, made some really good results, very impressed, he had the aqua mist kit in his.

He ran a 50:50 mix of water and meth, got the meth in big 25L cubes off his old man real cheap.

Meth didn't last long enough though, few laps around the track and it was empty. (5 L tank). He had a warning light on the water meth tank level though so he could come in before it ran out and he reached ping city.

My favourite part was you could touch the plenum after a hard run and it'd be cool to the touch like it had just come out of a fridge

[tridentt150v]

If you use the anti drain solenoid - and all boot mounts should use them, think hill parking and your motor full of WM - then the pressure is retained. The motor in my kit is always on but only pumps when there is a pressure drop, just like a fuel pump. The solenoid for this is at the motor.

I do agree though that the solenoid for the injector control could be better located for the SP kits. I've got a SIII and can control WMI using injector duty cycle and boost pickup.

The push in fittings are crap, they are OK if you never use them more than 2-3 times, but after that they will not grip and/or leak. I replaced most with straight bolt up fittings.

The hose is just plastic 1/4" air type hose and could be a better grade, but it works for now and is cheap to replace.

It would be good to compare the various kits and their performance edge, but I have to say that mine is still fine and I've had it for 18-24 months now. The aquamist website forum is better, europeans seem to get on there and talk about all sorts of stuff. The SP forum is less helpful, Americans usually only want to talk about their pickup trucks, but it is still OK. One thing, SP never had any direction to their website forum for any help etc, you had to find it yourself. I would have thought that they would promote it much better.

And my tank is still working fine - Mafia you must be the wrecking ball......lol

[GTScotT]

Hey Guys I thought I'd chime in with a picture i found ages ago when i was researching wmi, it's one of those a picture tells a 1000 words...

The only changes in blue yellow and green runs is they changed the ignition timing, which you can see from where the combustion pressure starts to increase. The timing with the water methanol injection turned on is somewhere between the yellow and red runs.

It's clear with the water methanol injection turned on that your peak combustion pressure is reduced, whilst increasing the average combustion pressures and most likely the combustion pressure at the angle where peak torque is made during a combustion cycle.

Regards

Jarrod

Thanks mate, after I had a good read of your explanation of the photo it really did tell 1000 words

[TiTAN]

LOL I wish I knew that about 2 days earlier. Nah I'm sure it will be fine.

One thing I am now wondering though.. And Titan should be able to clarify.. Does the system purge when your using the optional solenoid? Or still suffers from the same issue?

It cant be that bad really.. Surely the hose would fill up really quick and be fine if your careful with your first few boot fulls. I will go into my experiences when the time comes.

there is a small delay from when the system starts to when liquid comes out the nozzle but i have my solenoid ~1m from the nozzle.

[jet_r31]

Coolingmist have a fancy boot mount tank that they reckon won't suffer these issues but iirc they have the whole pump assembly attached so I don't think you can just buy the tank.

I'll post a linky later

Pretty sure you can just buy the tank..i'm sure i have seen it on ebay separate

cheers

darren

[rob82]

Simple science there mate..

When the water vapor hits the cylinder it will turn to steam, steam takes up a lot more volume than its equivalent in water and as it converts it will obviously increase cylinder pressure as it soaks in the heat.

So here's the process: Water quenches heat > turns to steam > steam increases combustion pressure (without the usual downside of added heat for the 'no shit' reason).

Static compression is cylinder pressure when cranking (normal comp test), dynamic compression is the effective compression ratio after you take boost/volume/VE/RPM into account (rocket science).

That being said, its rocket science 'just add water' edition

I understand the thermodynamics of what your trying to say but it doesn't make sense in reality. If water increased the dynamic comp then why don't you add it all the time? Surely you will gain hp everywhere? I'm not bagging water injection as a way of quenching chamber temps and slowing flame propagation rates but all the hype about it disassociating the hydrogen and oxygen and the water turns to steam which creates greater dynamic comp is a load of.

[GTRNUR]

I've recently enabled my wmi system again.

This time I am using 2 x 150's pre turbo and a single 300cc in the intercooler return line(600cc total, previous was about 800cc total). The pre turbo nozzles are to to drop air temps and improve turbo efficency, and post turbo to increase the octane rating/reduce knock.

I use solenoids for each set of nozzles. Ideally you want to have them as close to the nozzle as you can. Otherwise you get a dribble when they shutoff, as the plasic pressure hose does expand a little under pressure between the nozzle and solenoid. Dribbles are not good for the health of the turbo impeller wheels.

I can consistently log at least 15 degree air temp drops on the standard GTR (heat soaked) air intake sensor. As the sensor is too slow to react and the temp doesn't stabilise I really have no idea how low it goes.

The 50/50 mix doesn't appear to be affecting my AFR's at all with the current tune of 1.3 kg/cm boost. I am only injecting after 12lb manifold pressure (switch), as my goal is really to lower air intake temps when on boost, not to elevate the octane rating. I'd be using a progressive system if I was aiming for more power through more ignition advance.

There is no hesitation or noticable blip as the system comes on. (The previous larger nozzle setup I suspect would cause a momentary ignition flameout below 4500 RPM).

I will be able to produce some back to back dyno results next tune session to see how it responds with no tuning alterations. Based on the data logging of FCedit, knock is a little lower on average. To get more of a gain I think I should be injecting closer to 400-450cc before the plenum to get more of an octane boost effect (and have a progressive controller). Most of the spray from the 2 x 150cc pre turbo injection will be evaporating completely before it gets to the engine.

My previous nozzle configuration that injected 520cc post intercooler allowed 5-6 degrees more across the map when on boost(but had a ignition flameout issue occasionally).

As per the Aquamist forum information, the apparent ideal ratio is 25% pre turbo, 75% post turbo. This seems to work for me. WMI injector size is 15% of total fuel injecton flow at full load.

(Total injector flow) x (Injector Duty) * 0.15 = WMI Nozzle size

Eg: 6x700cc = 4200cc of BP98 pump fuel. 4200 x 0.90(duty) = 3780cc. 3780 * 0.15 = 567cc. Which means 140cc pre turbo and 425 post.

Injecting WMI does initially lower EGT's, but as someone else has already stated, it will also lower power as you are slowing down and cooling the burn. Its the same principal as running a street tune on race fuel, or just retarding the ignition of your street fuel tune 5 degrees.

Ideally you would tune the car for max power without WMI and aim for a target EGT, say 800-820 max at the dump pipes. Then turn on WMI and advanve the timing till your EGT's average the same and your knock readings are back to typical.

[zebra]

How much does it drop egts on your setup?