Question:

It seems to be general knowlege that a CAI system will give a noticable increase in power. I understand that it does this by lowering the charge temperature and this allows more air to be packed into the combustion chamber.

From what I read, water injection will also decrease the temperature of the charge, but WI by itself will not provide any more power.

Would I be right if I assumed that the reason CAI gives power and the WI does not is because the CAI also leans out the mix a little?

If the above is true, will the combination of CAI and WI be a good setup that will lean out the mix providing more power potential (assuming no other changes to the tuning), while the WI helps protect the engine from detonation?

 

This sounds like something very very dangerous. 13B-REW and Lean should not be in the same sentence.

 

I think you might misunderstand, I am not speaking of any wild air mod, I am speaking of a standard CAI mod.

 

The reason that a CAI will help power is because colder air is denser, thus you get more oxygen molecules to mix with the fuel for every intake charge that goes into the engine. (the main reason I see that CAI help with power is that they are far less restrictive than the stock airbox)

Water injection lowers the charge temps by evaporation of the water, but it doesn't add any more oxygen to the mix, so it doesn't add any significant additional power. You can use it as a safeguard against detonation, or tune for it (more ignition advance, more boost, leaner mixture) for more power.

Simply changing your intake with no other changes to the stock exhaust will not do much to the a/f ratio. The WI will help provide a buffer against detonation, however.

 

the main reason intakes will help make power is that like everything else on your car it is designed as a compromise. it is ment to be quiet first. not everyone who buys a new car wants to hear it work. with some simple mods the intake will become even more of a restriction.

 

Hmmm, Pardon me, but isn't that what I said?

 

Nope. You were asking questions. I was answering them by providing clarified information, because it's obvious you're not clear on their exact concepts. Including answering your last question.

 

Nice


Check out www.waterinjection.info

They have a wealth of information on water injection,

 

Logically you would think that if you slap water injection on your car you would gain more power since it makes the air colder and cold air is more dense. The reason it doesn't work that way is because with water injection you now have water in the intake track of your car where you once had oxygen. The colder intake temps are canceled out by the fact that you have less oxygen. In otherwords its a wash

 

Errr, more like a steam...

 

Actually, that's not the case. The amount of water injected into the intake tract compared to the amount of air ingested by the engine at WOT is pretty insignificant. The reason that it doesn't directly result in more power is that the air needs to be colder before the turbo pressurizes it in order for it to be "denser" and contain more oxygen. All WI does is drop the combustion chamber temps by evaporation; it doesn't make the intake charge any more dense.