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Water Injection:

Water injection is a method for cooling the combustion chambers of engines by adding water to the incoming fuel-air mixture, allowing for greater compression ratios and largely eliminating the problem of engine knocking. This effectively increases the octane rating of the fuel, meaning that performance gains can be obtained when used in conjunction with a supercharger or turbocharger, altered spark ignition timing, and other modifications.

The initial injection of water cools the fuel-air mixture somewhat, which may allow for more mixture to enter the cylinder. But the greater effect comes later during combustion when the water takes in significant amounts of heat energy as it converts from liquid to gas (steam), increasing piston pressure (torque) and reducing the peak temperature with its resultant NOx formation as well as the amount of energy absorbed into the cylinder walls. The duration of combustion is said to be longer.

An interesting side effect that has been reported by some is that water injection effectively "steam cleans" the engine interior, resulting in less carbon residue buildup. Glowing hot carbon deposits are a known cause of knocking.

Fuel economy can be improved with water injection, although the effect on most engines with no other modification, (getting your ECU tuned), appears to be rather limited or even negligible in some cases.

Control over the water injection is important. It needs to be injected only when the engine is heavily loaded and the throttle is wide open; as with other systems which need to monitor engine load, this can be determined by manifold vacuum, which is low when the engine is loaded and high when it is unloaded; however, provision must be made for starting, when the manifold vacuum is also low but water injection is undesirable.

• Reports of more rapid corrosion of the steel and cast iron components of engines to which water injection has been added suggest that more frequent oil changes, particularly when the engine does not experience sustained high temperature operation to evaporate any water from the oil, are prudent.

• Many water injection systems use a mixture of water and alcohol (usually 50/50), partly because the alcohol is combustible, while water is not; in addition, the alcohol serves as an antifreeze for the water.

Methanol & Water Injection:

The water injection section applies here as well, with the following info added in:

Methanol, also known as methyl alcohol, wood alcohol or wood spirits, is a chemical compound with chemical formula CH3OH. It is the simplest alcohol, and is a light, volatile, colorless, flammable, poisonous liquid with a distinctive odor that is somewhat milder and sweeter than ethanol (ethyl alcohol).

Methanol is a high octane fuel (113 octane*) that is extremely resistant to detonation. When using methanol injection, it is advised to mix with distilled water being that under-hood temperatures can turn methanol into steam being that methanol boils at 148.46°F (64.7°C) - this in turn can cause your car to not inject methanol.

Methanol & water injection is also an effective means of cooling the charge air. Methanol is the preferred alcohol due to its elemental properties (being that it's miscible), and is normally mixed with water to prevent evaporation. Methanol is typically injected before the throttle body.

This both cools the combustion process but adds additional high octane fuel to the fuel air mix raising the effective octane to levels high enough to push knock limited performance to new limits.

Methanol, unlike nitrous oxide or forced induction itself, doesn't add more oxygen to the charge, but by its low evaporation point changes from a liquid to a gas as its introduced into the air charge.

The evaporation process uses the heat from the intake charge to complete the phase change. The alcohol is also a fuel in the charge which will cause a rich condition if used in excess. Due to the lower intake temperatures and denser air charge more power is exerted from the engine.

"Extra" science information:

• Water and methanol are miscible in all proportions. (Miscible is the chemistry term that refers to the property of various substances, particularly liquids, that allows them to be mixed together and form a single homogeneous phase. Substances are said to be immiscible if they cannot be mixed together, for example, oil and water.)

• One of the drawbacks of methanol as a fuel is its corrosivity to some metals, including aluminum. It will eventually totally dissolve aluminum.

• Methanol is not the same as denatured alcohol. Denatured alcohol is ethanol containing a percentage of methanol (to make it unsafe/useless for human consumption but still useful for industrial processes. This is done in order to make it exempt from taxes that apply to potable alcohol).
• Info From Majin

Dangers:

Methanol is toxic by two mechanisms. Firstly, methanol (whether it enters the body by ingestion, inhalation, or absorption through the skin) can be fatal due to its CNS depressant properties in the same manner as ethanol poisoning. Secondly, it is toxic by its breakdown (toxication) by the enzyme alcohol dehydrogenase in the liver by forming formic acid and formaldehyde which cause permanent blindness by destruction of the optic nerve.[2] Fetal tissue will not tolerate methanol. Dangerous doses will build up if a person is regularly exposed to vapors or handles liquid without skin protection. If methanol has been ingested, a doctor should be contacted immediately. The usual fatal dose is 100–125 mL (4 fl oz). Toxic effects take hours to start, and effective antidotes can often prevent permanent damage. This is treated using ethanol or fomepizole.[3] Either of these drugs acts to slow down the action of alcohol dehydrogenase on methanol by means of competitive inhibition, so that it is excreted by the kidneys rather than being transformed into toxic metabolites.

The initial symptoms of methanol intoxication are those of central nervous system depression: headache, dizziness, nausea, lack of coordination, confusion, drowsiness, and with sufficiently large doses, unconsciousness and death. The initial symptoms of methanol exposure are usually less severe than the symptoms resulting from the ingestion of a similar quantity of ethyl alcohol.

Once the initial symptoms have passed, a second set of symptoms arises 10–30 hours after the initial exposure to methanol: blurring or complete loss of vision, together with acidosis. These symptoms result from the accumulation of toxic levels of formate in the bloodstream, and may progress to death by respiratory failure. The ester derivatives of methanol do not share this toxicity.

Injection Systems:

Some of the more well known systems are:

• Auqamist. Water injection systems, Methanol injection systems : Aquamist

• Coolingmist Water Injection, Methanol Injection systems | Coolingmist

• DevilsOwn DevilsOwn alcohol water injection- methanol

• SMC Welcome to SMC Enterprises

Freezing Point:

A good source of freezing point per water ratio can be found at

NuGenTec-The Art-n-Science of Specialty Chemical Blending and Development

Engine Damage:

Without a proper tune Injection can cause lots of damage to your engine And even with the right tune you still run the risk of the injection system failing causing your car to run at levels it is not possible to sustain and will cause immense engine damage.

Thanks to Majin for the first half of this faqs His format and information were top notch.

[halfelite]

More to come.

[Jwracing]

Here is a good artical on where to place your alcohol injection nozzle.
I found it usefull.
DevilsOwn Injection - Articles - Tech Articles - Where to locate your alcohol-water injection nozzle.

[halfelite]

Originally Posted by Jwracing

Here is a good artical on where to place your alcohol injection nozzle.
I found it usefull.
DevilsOwn Injection - Articles - Tech Articles - Where to locate your alcohol-water injection nozzle.

Nice find i will add it to the sticky.