Continued
Chemical Intercooling!
SOME BASIC UNDERSTANDING:
Recently over the past few years, water methanol injection has become more popular and is recognized as an invaluable addition for both gasoline and diesel forced induction engines and even naturally aspirated engines.
Water/Meth injection is also referred to as a “chemical intercooling”. It is more commonly used in forced induction setup because of the incredible cooling effects and added octane increase it adds to our regularly used pump gas.
Water/Meth Injection has the potential to reduce air intake charge temperatures by 50-200+ degrees F almost instantly. This equates to a cooler denser air charge for a greater power in the combustion chamber and also largely reducing the problem of engine “knocking” and allowing the owner to run higher levels of boost, compression and more aggressive timing.
Depending on the amount injected and the type of mix used (pure water, pure methanol or a mix of the two), gains up to 10-25+ points in octane can be achieved.
What does this mean?
It essentially means that you can make 91 octane pump gas act like 105-116 octane racing fuel in your engine. In return you pretty much get rid of the need for expensive racing fuels, which can cost a pretty penny. Its also far more effective, affordable and convenient to those expensive octane booster fuel additives as well, which basically do nothing once you get past the hype.
WHAT CAN BE USED FOR THE SYSTEM:
Water and various grains of alcohol, methanol, ethanol and isopropanol, are the primary fluids which are commonly used in a water methanol injection systems.
The most common types of alcohol used in water methanol injection systems are of methanol grains. Methanol is cheaper to produce than ethanol, thereby making it the more desirable between the two to use. Methanol is produced primarily from natural gas, wood or coal. While ethanol is produced from sugarcane or corn.
The main difference between methanol and ethanol is that methanol has a lower caloric weight (the amount of energy available to burn when combusted), higher specific heat (takes more heat to burn the mixture) and a high heat of vaporization (when vaporized can cool down intake air temps dramatically). Ethanol is generally the same characteristics and properties as methanol, but does not cool down the intake charge as well and as mentioned above costs a good amount more then methanol.
NOTE: For engines that are fueled solely by methanol, such as race engines, it’s not uncommon to see ice form on the outside of the intake manifolds during operation. Methanol is able to cool down the intake air temperatures entering the cylinder head so well, that when used as the primary fuel on a forced induction engines, an intercooler is sometimes not needed. Most surprisingly, engines can also be ran without a radiator. This being an example of the cooling effects offered by methanol in the more extreme builds.
BIG NOTE: While water methanol injection can be extremely beneficial to both NA and FI builds, proper installation, delivery, control and tuning are VASTLY important to making it all come together safely and to get the best out of the entire thing.
PRELIMINARY CAUTIONS TO TAKE NOTE OF:
It's recommended that a maximum mixture of 50/50 mixed of water and alcohol, as it will not be a flammable liquid in this state of mixture. Using mixtures with greater percentages of alcohol will become a flammable liquid and use of stainless steel lines should be used. Of course this doesn't always happen. as i'm using a 70/30 mix in my car. But just note that you need to be careful when using mixtures greater than 50/50 mix and accept and acknowledge all consequences that come with mixes over that percentage.
TUNING:
**Tuning Tip** Since alcohol is a fuel, when using mixes with higher percentages of alcohol, expect air/fuel ratio to richen up more then when used with mixes containing lesser percentages of alcohol with greater percentages of water. For this reason, many user’s will actually prefer using a much lower percentage of water/alcohol or 100% water. Depending on the application this can be just as effective while not affecting the air/fuel ratio as greatly as does mixes with greater percentages of alcohol. We highly recommend the use of a wide band o2 system to monitor air/fuel ratio and aid in tuning your engine.
There is no set "accepted" change in AFR. as every engine is different and everyone may not be running the exact same mix. so this is where you're Wideband will come into play.
Info about your wideband.......
USE IT, LOVE IT, WATCH IT, USE IT SOME MORE, AND LOVE IT SOME MORE!!!
the wideband is a godsend to saving motors and tuning properly whether its built into the car from the factory or you install an aftermarket one. USE IT!
TUNING TECHNIQUE:
This pertains to how you go about tuning the car once you are using water/meth injection. There are many ways you can do this. Since we all no know that Water/Meth Injection raises octane and cools intake charge temps heres some route you can take at tuning
1. go with aggressive timing
2. increase boost with moderate or decreased timing
3. lean out the air/fuel ratio more than it was prior to using water/meth injection
4. lean out AFR and increase boost a PSI or two
5. run a lil richer AFR with slightly more aggressive timing and a cople pounds of boost increase.
thats just an example. what you do depends on how you want to make power and how much you want make and what you or the tuner feels comfortable with doing.
You also have to be aware of how your car is reacting to the changes. is it sluggish, does it feel like its missing a bit. lost power, and etc. these can all be symptoms of a couple things.
1. timing needs adjustment
2. AFR is too rich
3. AFR is too lean
4. spraying too much water/meth at too low of the boost pressure/onset
5. not spraying enough for the tune you are trying to run
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