Richard L

iTrader: (5)

My name is Richard Lamb and responsible for the technical development of the aquamist range of water injection system, we are located in England.

I am here to help solving any application issues regardless of mechanical, electronics and general tuning problems with aquamist product. I have posted a similar thread on the NASIOC forum and have been successful in my view.

I cannot deal with sales at it is handled by our sole importer and distributors in the USA.

I know that the usage of water injection is much less on EVOs communitiy but there are enough people here for me to justify spending time and effort to help you achieving the best outcome possible.

There are so many tunnig tools available for the evo and please take things gently as I don't know all of them, but I promise to work it through.

Looking forward to the first reply.


Richard Lamb

SlowCar

iTrader: (4)

Richard: Can you achieve the capability of pure MeOH injection with just water alone?

Richard L

iTrader: (5)

Thank you for the question.

No contest, water cannot compete with alcohol when the purpose is for supplimenting the pump fuel's octane rating. It is like comparing injecting gasoline against injecting methanol or injecting methanol and nitromethane.

When the comparison of the two liquids is used for in-cylinder cooling, water will score better. But the contest is not very glamorous. I give you an example, when we annouced the aquamist pump can be re-sealed to run nitromethane and methanol mix, the post count on our forum went up instantly - power producing statement rocks in this industry.

Alcohol is a fuel wth excellent octane rating and since it requires injecting twice the amount to produce the same power as gasoline, the cooling effect is doubled without taking account the better latent heat value.

Some alcohol draster requires a dose of anti-freeze in the inlet tract to avoid the throttle plate freezing up. The freezing up is due to the water vapor in the ingested air.

There are some crossovers between alcohol injection and water injection systems if you are injecting a mxiture of the two. If you are comparing systems, it will be a totally different topic and answers altogether.

SlowCar

iTrader: (4)

What will be the best v/v% H2O/MeOH combination in your opinion?

propellerhead

iTrader: (3)

Welcome to EvoM Richard! I've enjoyed your thoroughly technical and helpful posts over on the water injection forums.

You and I traded some messages back and forth with regards to the compatibility of the Aquamist system and pump with methanol. At that time you mentioned that it would be possible to manufacture a pump using teflon seals which would be somewhat impervious to the corrosive effects of 100% methanol. I see above that you are facilitating this upgrade.

Would it be possible for the end user to upgrade a pump with teflon seals or would this type of modification require the pump to be shipped back to you for tear down and reassembly? Aside from hoses and storage tanks, are there other componants of the system such as the HSV or pressure switch that would need upgrading as well?

Richard L

iTrader: (5)

I am not very experience on this subject but it appear that 50/50 mix is what people normally use with good result.

The cooling capacity of alcohol appears to be good for inlet air cooling (lower boiling point than water) and water is used for in-cylinder cooling. This is the way how people distill spirits traditionally.

I have a few charts that will slow the overall cooling effect of the "mix" and "water" alone. If anyone is interested, I will dig it out and post them here.

Richard L

iTrader: (5)

Hello Propellerhead, thanks for chiming in.

I have had quite a few emails from the evo owners over the years and they are not happy people, it appeared that there isn't many tuners in the evo community willing to tune with water injection. When they were encouraged to do it on their customer's request, they refused to tune it properly when there are failsave mechanism in the system and yield poor results.

We are making telflon seals available to all who want it and willing to change it themselves - totally free. Since all the aquamist pump components are machined parts, dis-assembling and reassembling is quite simple. Here is a link to that effect posted by one of our users.


The other wetted parts use EPDM seals so running 95% methanol presents no ill effect. But my main concern is flammeability - methanol burns without a flame and colour. I would suggest anyone that run over 60% methanol mix should use teflon hose and compression fittings (available at northern tools.com).

SlowCar

iTrader: (4)

it would be nice if you could post them. Thanx!

Richard L

iTrader: (5)

The following charts are calculated based on:

10Kg of air, Gasoline's latent heat capacityof 350KJ/Kg
Water's latent heat capacity of 2256KJ/Kg
Methanol's latent heat capacity of 1109KJ/Kg

Injection water at different ratio to fuel at 100% water and 75% Water/25% Methanol. You can see the at 100% water injection, only 3% of w/f fuel ratio is enough to replace 2.5 point of a/f ratio (dotted line). As soon as 25% of Methanol is added, the a/f ratio is dropprd to 12.0 - loosing some cooling capacity




Each of the following chart show a 25% percent increase in Methanol concentration of the mix.



lastly, just methanol is added and no water. The chart on the right is 100% water




The two charts show (first and last) that you will require to inject twice the amount of methanol to equal the latent heat of water alone. Methanol is relatively low cost and very effective as a coolant so what is the problem?

When higher concertration of methanol is injected, you need to lean your engines a/f ratio to accomendate the extra fuel or your engine will bog down and loose power. Consequentially - one runs the risk of putting the engine into heat stress if the supply of methanol is suddenly interrupted. Injecting water does not affect the a/f ratio. It appears that 50/50 mix has the best of both worlds.

In either cases, having a good w/a injection system with reliable "system fault" diagnostic capability is essential especially if you are running a high concentration of Methanol.

4TUN8

iTrader: (18)

What would you suggest someone run if they weren't interested in running higher boost pressures?

Richard L

iTrader: (5)

Thank you for posting more querstions.

I am not sure if I understood the question. Are you saying whether water/alcohol injection is necessary if you are not going to increase the boost pressure?

SaabTuner

I personally think the ratio of meth/water should be taylored with the thought in mind that, while methanol only cools half as well as water, 4.8 times more of it can evaporate at 40*C before becoming saturated. (If you had even 60% ambient humidity, double that to 9.6 times more methanol that can evaporate.)

The nicest part about injecting water is that it is a clean way to replace excess fuel, and it is CARB legal in California, unlike methanol injection. (Of course, you could always just tell them it was water and I doubt they'd actually check.)

I personally like the idea of a pre-turbo injection setup with water only because it significantly reduces the pumping effort from the turbo. Generally that means your wastegate will be open more at full load, which reduces backpressure, and your turbo may spool a bit faster. Some people seem to find that you can also use a larger turbine A/R without the normal sacrifice in spool up.

The reason for this unusual boost in turbo performance is that the water boils as it passes through the compressor, absorbing heat from the air. "Normal" compressor exit temperatures can be over 300*F which means the air is NOT very dense and must flow at either very high pressure or very high speed to reach a given mass-flow. By keeping the air denser all the way through the compressor, the turbo doesn't need to spin as quickly to accellerate the air.

However, if you have the injection come on suddenly (going from no water to full water fast) then your wastegate tables may get a bit hairy at the transition because the wet-compression affects the requisite wastegate duty cycle for a given boost pressure. If the WI transition is well below maximum boost it shouldn't hurt anything, though the throttle response might become "snappy". This snappy behavior could be reduced by mapping the WI to come on slowly as boost rises.

[/end-hijack] Sorreh!

-Adrian

gunzo

iTrader: (2)

hi, interesting thought.. any ideas on the droplets hitting the compressor at 80000rpms or so? maybe not short duration but i would think there maybe some damage to the fins with prolong use??

if theres no side effects thats certainly a very good idea at lowering temps!

welcome aboard richard..
any comparisons with those sparys running off shureflo pumps??

aquamist = 1st rate customer service

EVO8LTW

iTrader: (41)

What is an example of a "reliable system fault diagnostic capability system" for an Evo? Does Aquamist make anything that is a direct application for the Evo?

I've heard people make reference to various home-engineered solutions, but they all require a knowedge of electronics. I'm interested in a system that has safety provisions and bolts/plugs right in.

I do have an electronic boost controller, so if there were a way to cut power to that upon a fault with the water injection, that would immediately lower boost to wastegate levels.

dryad001

iTrader: (27)

Use the utec to disable it.