Charge Cooling!

[BoostedFC]

Some basic info on charge cooling.

An intercooler (sometimes referred to as an aftercooler) is designed to remove heat from the compressed air coming from the supecharger (or turbo) before it enters the engine's induction system. An intercooler works just lie a radiator - air is cooled by fins, bars, louvres, and plates inside the intercooler that are cooler than the compressed air coming from the supercharger. The reduction in air temperature increases the density of the air (more air molecules per cupic foot), which consequently increases your engine's ability to make more horsepower and torque. The decreased air temperature allows you to run more boost on a given octane of fuel before detonation occurs..

What's up with the terms?

The term 'intercooler' comes from days when they were first used on twin turbo aircraft engines. With two turbos, the air charge would get VERY hot - it was heated by the first turbo, then heated again by the second turbo. To combat this double temperature rise they placed a heat exchanger in between the two turbos and called it an "intercooler" because of its location in between two turbos. When this same kind of heat exchanger is used on a single turbo or supercharger, it is located after the supercharger, and should technically be called an "aftercooler" because of its location after the single turbo or supercharger. These terms didn't seem to stick, though. The term 'intercooler' caught on and became almost universal for all heat exchangers regardless of their position. The term 'aftercooler' became synonymous with air-to-water coolers because this is the term Vortech uses to describe their coolers, which are water cooled. So while technically incorrect, we will still use the popular terms 'intercooler' to mean any air-cooled charge cooler and 'aftercooler' to mean any water-cooled charge cooler.

Why Intercool?

There are several important benefits to intercooling that have resulted in their increased popularity in recent years. The most significant advantage is that intercooling increases the detonation threshhold because of the cooler air charge, meaning you can run more ignition advance for higher performance, or run lower octane fuel before experiencing detonation. This makes intercoolers very desirable for those looking to get the most out of their street vehicles on pump gasoline. The cooler air also allows your engine to run slightly cooler, reducing the chances of overheating. Intercoolers also enable your engine to produce more horsepower because of the denser air charge being delivered to the engine's combustion chamber.

Don't assume, however, that you can simply bolt an intercooler on to your supercharged engine and expect power gains with no other changes to the system. Intercoolers do create some internal drag causing a slight reduction in boost, and can also cause the engine to run lean (knock) due to the denser air charge. These problems are easily corrected and should not cause concern, however they cannot be ignored. Boost pressure can be brought back up (actually you'll probably want to run substantially more boost than you did with a non-intercooled application) using a smaller supercharger pulley. The smaller supercharger pulley will spin the supercharger faster and increase its output. Make sure your supercharger is designed to handle these higher boost levels. Correcting the air/fuel ratio to compensate for the denser air charge can be done with larger fuel injectors, recalibrated FMU, larger fuel pump, adjusting the mass air meter, etc.

Intercoolers... Aftercoolers... What's the difference?

In order for an intercooler to effectively cool the air that passes through it, the intercooler itself must be cooled by some external means. Most intercoolers are cooled just like your engine's radiator - air flows over the outside of the intercooler's fins, which in turn cool the air inside the intercooler - hence the name Air to Air Intercooler. Some intercoolers, however, are cooled by water instead of air, in which case they are generally called aftercoolers, or Air to Water Intercoolers. The benefit to an aftercooler is that air passing through it can be cooled more than in a traditional air/air intercooler if very cold water and ice are used to cool the intercooler - in fact, some aftercoolers chill the air to below ambient air temperatures even after it has been compressed by the supercharger. The reason aftercoolers are more effective in cooling the air charge is because water is a much better conductor of heat than air - in fact water conducts 4 times as much heat as air! The obvious drawback is that with time, the water will heat up to the temperature of the air passing through it, and its ability to cool incoming air goes away. Some aftercoolers, however, use a small radiator to cool the water that runs through the system, making them ideal for street use as well as racing. For drag racing applications aftercoolers packed with ice work very well because they only need to work for around ten seconds or so (hopefully) before you shut down and head to the victory podium. For milder racing and street applications air/air intercoolers or aftercoolers with radiators are more practical as their ability to cool incoming air is not reduced with time.

When is it right to intercool?

Obviously, intercoolers only work with supercharged or turbocharged vehicles where there is a substantial difference in temperature between the air entering the engine and the cooling medium (the intercooler). Because superchargers heat up the air significantly as they compress it, it is possible for there to be a very large temperature difference between the intercooler (ambient air temperature - 80F degrees or so) and the compressed air (200F - 350F degrees). Superchargers with higher boost will create a hotter discharge, so as you increase your boost, the effects of the intercooler become more and more noticable. In general we would not recommend intercoolers on supercharged engines with less than 8-9psi of boost, as the benefits will not be substantial. Essentially, run an intercooler when only when you running peak boost (i.e. any more boost would cause detonation) for the octane of fuel you use. Intercoolers work well in both warm and cool climates and work exceptionally well on marine applications because of the easy access to cold water.

Don't intercoolers restrict the flow of air into the engine?

Yes. Any time there is an obstacle in the way of the air flowing into the engine (like an intercooler fin or louvre), a pressure loss will result. Today's intercoolers are very effective in minmimzing this pressure loss so that the benefits obtained by cooling the discharge temperature normally outweigh the 1-2psi (approximate) loss in air pressure, which can be regained by running a smaller pulley and increasing the output of the supercharger or turn the knob on the boost controller for turbos.

[BoostedFC]

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