tresturbos2

This company makes some far-out claims.

If it were true, I'd think we would have heard a lot about it, given that they've been around for 30 years.

What about the concept? Any mechanical engineers in the group?<ul><li><a href="http://www.aquatune.com/overview.html">http://www.aquatune.com/overview.html</a</li></ul>

RangeR BoB

Water injection has been used for most of the last century for quelling detonation in a high compression motor. The injection of water does a couple of things:

1) keeps your cylinders clean of carbon buildup

2) reduces detonation.

To understand why it helps with detonation, you have to understand what it is preventing. Detonation is caused by the collision of two or more flame fronts within the combustion chamber. As the flame fronts collide at supersonic speeds, they make audible sounds (the pinging) and the energy released by the fuel goes into the collision, not pushing the piston down the bore. The suddenness of the shock waves breaks parts. Detonation is bad.

The presence of the unburnable but high specific heat water helps to buffer the burn rate of the charge, which in turn helps its apparent octane ratio.

The water in the combustion chamber cools the hot spots in the metal which can lead to preignition.

Water has a very high specific heat. Finely atomized droplets of water have a high surface area for their volume and so they evaporate quickly in the air stream, which absorbs energy from the moving intake air, cooling it.

Formula 1 engines in the turbo era depended heavilly on water injection to allow them to get 1400 hp for qualifying out of a 1.5l motor.

The detractors of water injection are many. Usual comments fall into the categories of "you are running too much spark advance anyway" "Water injection is a crutch for bad tuning" or "you are running too lean"

All of these are true statements when applied to INDIVIDUAL cases, but none of those reasons negates the fact that WATER INJECTION WORKS. Sure, there are a lot of badly tuned engines out there. Sure many experimenters w/o access to good tools cannot get their spark or air/fuel ratios right. Water injection is a crutch for them.


How about a perfectly tuned car naturally aspirated motor with everything right? What happens if you slap on a WI system? Not much presumably. Its the same as burning premium in a car with 8:1 compression. No gain realized. The evaporation of the water will increase your charge density a bit and you will have squeaky clean combustion chambers.

However, say you are thrashing your chipped Audi around and you have VWtool hooked up and you notice that you are dropping 4 degrees of spark advance because the knock sensor is detecting pinging. If you run a properly set up water injection (Not an "uncle fred" system, but a well engineered system like the AquaMist appears to be) that introduces a small quantity of properly atomized water droplets into your intake, you will see measurable gains.

Even better is if you then retune the car to take advantage of the water injection. More boost. More spark lead. You can generate more power with a PROPERLY TUNED car with water injection than you can without, burning the same gasoline. That is a proven fact.

A well thought out water injetion system will have:

o a high pressure pump (not a low pressure windshield washer pump or the like)

o a fine-atomization nozzle, located near the intercooler discharge (not ahead of the intercooler!) to give the longest dwell in the intake air stream before the valves so you get the most cooling effect, as long as your intake system is capable of wet flow without too many disruptions. Audi manifolds qualify as decent in regards to wet flow ability.

o a controller that is able to take in signals like boost and rpm to determine the amount of water to inject.

They are not rocket science, nor are they a miracle. They do work, and can give very measurable gains when set up right. I plan on integrating a WI system on my motor as I push it over 300 HP.

I don't work for AquaMist or have any financial stake, I just don't like seeing a useful tool getting a bad rap.

I hope this helps!

WClark

Basically injecting water does 2 things:

1) in the intake manifold (fine mist injected anywhere in the intake air system) it cools air making it more dense.

2) in the combustion chamber (coarse particles injected in intake manifold) it cools hot spots making combustion more effective.

There are a couple UK outfits doing systems that are pretty sophisticated.

Bollinger

"Its a hydrogen cell processor".

Bull.

It is companies like this one that give water injection a bad name. Water injection mainly helps cool the intake charge. This is how it reduces NOx emissions, this is how it reduces knocking.

If you use water injection, you get some of the benefits of higher octane. You might be able to run more spark advance. You might be able to run more boost. You might be able to run higher compression ratios.

But I think it is all a waste of time. If you are going to inject something to cool your intake charges, inject nitrous oxide. It will cool the charge and add oxygen, and it really isn't much more complex than water injection.

RangeR BoB

But that's not the fault of water injection. That's a get rich quick system. Thus my post below.

"something like nitro colliding with glycerine..."

ROTFLMMFAO!

Geez that's pseudoscience if I ever heard of it.

$345! Man that's a lot of $ for something that won't work. Its basically an air bleed.

CharlieGSanD

i like the one about why a ferrari and a harley sound diffrent

that was you right?

steved

Stephen Hawking touches on performance claims in a recent British publication, citing the Uncertainty Principle and the incidence of customer funds travelling at the speed of light into the black holes of the aftermarket. SD

WJM

you cant just toss it on and get ALL the benefits. Aircraft engines run at smaller RPM range than cars do so the application is easier. If you want to wash out your cylinders though...go ahead toss it in. Steam clean your engine =)

JayP

Olds sold the water/alch mix, called it RocketFuel!

The engine wasn't strong enough to pull the big boats, so they bumped the compression resulting in pinging. Nothing ever worked and GM sold the engine to Rover where it made its way into stodgy Rover sedans, Morgans, MGBs, Range Rovers, TR8s and a handful of TVRs, Marcos and other cottage cars.

Class dismissed.

RangeR BoB

I sometimes wonder if I ma just blathering to myself, but its nice to know that folks appreciate what I write.