Water Injection, declined in popularity, why??

[j_jza80]

In Ireland we only have 95 octane so was using it to help towards detonation rather than as a performance gain and to keep my internals nice and clean

 

Wouldn't an octane booster be a simpler solution?

[Wez]

Wouldn't an octane booster be a simpler solution?

 

I know when I tried octane booster and WI with a 50/50 meth mix together the motor really wasnt happy, had to disable the WI until the octane booster had run out.

[Chris Wilson]

Well it wouldn't be, squirting unregulated amounts of combustants into the intake is not going to do the fuel mixture, so carefully mapped in the main ecu, any good at all. Octane booster should go in the fuel, in a controlled percentage.

[Chris Wilson]

After reading this I'm going to get one for the rex... I said I would never try and increase power when I bought it but going for 500+ bhp with few mods to the fuel system and wi kit

 

 

My RX-7 FD would show 20% higher EGT's if I turned off the (Aquamist) WI when on a track day in warm weather. Intake plenum temps went up an even higher percentage. Used sensibly I think WI is fabulous. Used to eke out the last degree of advance, or the weakest mixture not commensurate with det, with the WI running is asking for trouble when it croaks or runs out of water...

[msupra1]

I'm in Canada and our highest grade pump fuel is good for about at the most 1.2 - 1.3 bar.

 

I just finishing my tuning a couple weeks ago after installing cams and AEM Version 2 meth kit.

My tune on the AEM V2 has a switch for 2 maps, one for straight pump gas, and one for pump/meth.

 

 

The straight pump gas tune on a Borg Warner S366 turbo made 565bhp at 1.2 bar

I run 60/40 mixture of meth/water and the final tune made 695bhp at 1.65 bar. That's with zero detonation/knock.

We could have pushed more power out of it but it was dialed back for a conservative tune.

 

We also did some testing. At 1.1 bar the car made about 540bhp on pump gas.

With the meth kit spraying, at 1.1 bar it made 585bhp

 

I ultimately wanted the meth kit to run more boost, as that's the only real way I can make more significant power. The pump gas is limiting.

 

The tuner said running 100% meth is an option and it will make more power but I met my power goals so I'd rather stay safe with a mixture.

All in all I'm very happy with the results. I had my AEM V2 ecu updated to the latest firmware to get some failsafe's setup in place.

Edited April 23, 2015 by msupra1 (see edit history)

[costas1]

i have an aquamist (ERL 1s) on my car but i think it stopped working some years ago..tried to find out what happened took it to a few garages but noboby manage to find the problem so it just sits there on the car dead.. the pump seems to work when you supply it with 12v charge (spits actually)..the pressure sensor seems to be fuctional (tested with voltometer)..the tank has still liquid in but when the car is running the hose is half fulled with that..seems it does not reach the nozzle..maybe the pump is dead and will not push the liquid harder..dont know

[Chris Wilson]

Pull the hose off the jet and run the pump, does water come out? Sometimes the pump needs priming if its been allowed to dry out, use a squeezee bottle to pump pressurised water into the inlet side of the pump with it running to "get it sucking". Sometimes the controller in the pump died (water on the PCB board corroded the copper tracks or worse).

[costas1]

thx chris.. as said took it to a few garages nobody found the problem..we actually took the pump apart and checked the electronic plate inside..seemed to be ok..but when on car nothing seems to work..so i quit trying a couple of years ago..maybe i will try again one last time following your instructions..its a petty though cause it seems to be a good setup as you mentioned above

[Chris Wilson]

The early pumps were a bit unreliable, late ones seemed a lot better. Aquamist seem to have over complicated the latest set up, IMO.

[costas1]

exactly..and quite expensive also..here most of the people use the AEM kit

[Chris Wilson]

That used to be based on a crop sprayer pump that is far from ideal for WI, unless they have changed it?

[add heywood]

My RX-7 FD would show 20% higher EGT's if I turned off the (Aquamist) WI when on a track day in warm weather. Intake plenum temps went up an even higher percentage. Used sensibly I think WI is fabulous. Used to eke out the last degree of advance, or the weakest mixture not commensurate with det, with the WI running is asking for trouble when it croaks or runs out of water...

 

Yeah I'm not squeezing every last bit out if the setup, but would like it to get over the 500bhp (69 more than what I have now).

[Harvey]

have just read this thread and although i get the concerns of some over the water running out or the pump failing there are easy solutions to this? i am not an expert but working with refrigerant gas i understand how liquids can be used to transfer or dissipate heat which can only be a good thing in charge air temps? surely its only doing the same as when you drive on a cold foggy morning and your engine quite happily burns all that moisture and goes like stink!!! will be looking into WI very soon and thanks to chris for starting the debate and to everyone else that has posted their thoughts as ive learnt a lot from it :-)

[Chris Wilson]

Here's something I posted ages ago.

 

Water injection serves 2 closely related functions on a turbo engined

car. Firstly it cools the charge air temperature by utilising an effect

known as the latent heat of evaporation. This property can be self

demonstrated very easily. If you pour something that evaporates quickly

like petrol on your hand it feels very cold. This is the rapidly

vaporising spirit removing heat from your skin and bloodstream by the

aforementioned process. By spraying a very finely atomised mist of water

into the inlet of a turbo engine when under boost conditions the

evaporation of the water into steam causes a temperature reduction in the air and

fuel intake charge. A cold charge is less likely to be subject to

detonation than a hot charge. A cool charge is also denser, able to

carry more air and fuel mix per unit of volume. These 2 properties of

water injection allow either less chance of detonation at a given boost,

maybe allowing lower octane fuel to be used, or to allow a rise in boost

pressure usage without detonation. These are very desirable goals for

any modifier of a turbo engine, or one using an engine mapped to run

on a higher octane fuel than generally available in the UK. Japanese

import turbo cars for example.

 

People ask whether squirting water into an engine causes corrosion. In

fact this is not a problem, the combustion temperatures under boost

ensure the water is turned instantly to steam and is ejected out of the

exhaust. The water mist is injected only when high boost is sensed via

a supplied pressure sensor switch. The basic combustion process of

hydrocarbon fuels causes LOTS of water to be generated anyway, which is why cars

not driven on regular long journeys will rust out a mild steel exhaust

system from the INSIDE out. If water is added in the correct volume, via

the supplied, calibrated jets, this is not a problem.

 

Even when used alongside a larger or more efficient intercooler, or

indeed when an intercooler is used in an application where one was not

present as standard, water injection can and does increase charge cooling

still further. Water can be stored either in the existing windscreen

washer bottle or in a separate, dedicated, container. In cold conditions

it is essential to add an anti freeze additive to the water to stop pump

damage through freezing. Windscreen washer additive serves this purpose

fine and the engine won't mind ingesting this solution at all. Or you

can add neat methanol, which is usually the anti freeze additive in

washer fluid anyway. Using a 50 / 50 percent by volume water / methanol

mix will actually help increase the octane of the intake charge, as an

added benefit. As a yet further advantage the latent heat of evaporation

of methanol is extremely high. A win / win situation. It is not however

obligatory to use methanol as an additive. All components of the water

injection kit that are in contact with the fluid are stainless steel or

able to tolerate water and methanol or screen washer additive without

degradation. A properly set up system does not use a vast amount of

water, in fact a modern car sized screen washer bottle used also for the

water injection reservoir will suffice admirably. A water filter is

included to keep any sludge out of the pump or jet. This should be

checked regularly for contamination and blown out if residue is

apparent within.

 

A more technical explanation:

 

Let us take a quick look at ignition. Those who have a Heywood can look it up

- mines on loan so going by memory. The first thing that happens is a plasma

cloud is formed by the arc consisting of super heated electron stripped atoms.

When this cloud "explodes" a ball of high energy particles is shot outward.

 

The highest energy particles are the hydrogen atoms - and they penetrate the

charge about 5 times as far as the rest of the particles. As they lose energy

and return to normal temps - about 5000 k - they begin to react chemically

with any surrounding fuel and oxygen particles. The effectiveness of spark

ignition is directly related to the availability of free hydrogen. Molecules

containing tightly bound hydrogen such as methanol, nitromethane, and methane

are far more difficult to ignite than those with less bonds.

 

During combustion - water - H2O ( present and formed ) is extremely active in

the oxidation of the hydrocarbon. The predominate reaction is the following:

 

OH + H ==> H2O

H2O + O ==> H2O2

H2O2 ==> OH + OH

Loop to top and repeat.

 

The OH radical is the most effective at stripping hydrogen from the HC

molecule in most ranges of combustion temperature.

 

Another predominate process is the HOO radical. It is more active at lower

temperatures and is competitive with the H2O2 at higher temps.

 

OO + H ==> HOO

HOO + H ==> H2O2

H2O2 ==> OH + OH

 

This mechanism is very active at both stripping hydrogen from the HC and for

getting O2 into usable combustion reactions.

 

Next consider the combustion of CO. Virtually no C ==> CO2. Its a two step

process. C+O ==> CO. CO virtually drops out of early mid combustion as the O

H reactions are significantly faster and effectively compete for the available

oxygen.

 

Then consider that pure CO and pure O2 burns very slowly if at all. Virtually

the only mechanism to complete the oxidization ( Glassman - Combustion Third

Edition ) of CO ==> CO2 is the "water method".

 

CO + OH ==> CO2 + H

H + OH ==> H20

H2O + O ==> H2O2

H2O2 ==> OH + OH

goto to top and repeat.

 

This simple reaction accounts for 99% + of the conversion of CO to CO2. It is

important in that fully two thirds of the energy of carbon combustion is

released in the CO ==> CO2 process and that this process occurs slow and late

in the combustion of the fuel. Excess water can and does speed this

conversion - by actively entering into the conversion process thru the above

mechanism.

 

The peak flame temperature is determined by three factors alone - the energy

present and released, the total atomic mass, and the atomic ratio - commonly

called CHON for Carbon, Hydrogen, Oxygen, and Nitrogen. The chemical

reactions in combustion leading to peak temperature are supremely indifferent

to pressure. The temperatures and rates of normal IC combustion are

sufficient to cause most of the fuel and water present to be dissociated and

enter into the flame.

 

As can be seen above, water is most definitily not only not inert but is a

very active and important player in the combustion of hydrocarbon fuel.

Ricardo and others have documented that under certain conditions ( normally

supercharged ) water can replace fuel up to about 50% and develop the same

power output, or that the power output can be increased by up to 50% addition

of water. This conditions were investigated by NACA and others for piston

aircraft engines. It is important to note that these improvements came at the

upper end of the power range where sufficient fuel and air was available to

have an excess of energy that could not be converted to usable pressure in a

timely manner.

 

As a side note - Volvo recently released some SAE papers documenting the use

of cooled EGR to both reduce detonation and return to a stoic mixture under

boost in the 15 psi range - while maintaining approximately the same power

output. Notice - they reduced fuel and still get the same power output.

 

When you consider that EGR consists primarily of nitrogen, CO2, and water ( to

the tune of about two gallons formed from each gallon of water burned ), you

might draw the conclusion that it also was not "inert". They peaked their

tests at about 18% cooled EGR - which would work out to about 36% water

injection and got about the same results under similar conditions that the

early NACA research got.

[pf85]

Resurrecting an old thread...

 

So another few years have now passed, what are people's opinions of water meth kits now - are they still worthwhile or is there a more prefered method to keeping the cylinders cool whilst improving performance?

[Wez]

Resurrecting an old thread...

 

So another few years have now passed, what are people's opinions of water meth kits now - are they still worthwhile or is there a more prefered method to keeping the cylinders cool whilst improving performance?

 

 

Advances in technology now mean you can run a flexfuel sensor and suitable ECU and just pour some meth into your fuel tank for better gains

[Jellybean]

Advances in technology now mean you can run a flexfuel sensor and suitable ECU and just pour some meth into your fuel tank for better gains

 

Methanol is expensive and hard to obtain , thats the problem

[Wez]

Methanol is expensive and hard to obtain , thats the problem

 

https://www.jennychem.com/shop/methanol-bio-diesel/803-methanol-9985-new-210ltr.html

[JamieP]

Methanol is expensive and hard to obtain , thats the problem

 

 

Methanol is well cheap, can get for like 50P a litre

[Jellybean]

I have a flexi fuel sensor installed but Problem is getting methanol in Ireland , VP M1 is the only one I know of here plus is it not very carcinogenic

 

How many litres do you add to a tank? We only have 95 octane here

 

Storage of a large amount is also an issue

 

65 euro for 19 liters of methanol here

 

Companies here are reluctant to sell it as , Petrol station owners are using it to dilute petrol , launder fuel

Edited March 5, 2019 by Jellybean (see edit history)

[Swampy442]

Used it in a TDi track car, helps calm the smoke a bit. As said above its dirt cheap and readily available, if anyone wants some I know a great company in Lincoln

[Jellybean]

How many litres did you use, I calc 24litres with 95 octane will result in 100 mark

 

Methanol is roughly 110 octane from what I read

 

In terms of grades of methanol, some you need to avoid?

 

These guys appear to have alot of different grades

 

https://www.fishersci.ie/ie/en/products/I9C8K43R/methanol.html