Water Injection system used in the video: www.snowperformance.eu/en/wat...
Here we have a tank. We are going to put this tank in the car and fill it with water. Here we have a pump. This pump will take water from the tank, pressurize it, and send it to this little nozzle which will inject the water inside the engine.
How does injecting water make more power? Water is an incompressible incombustible liquid after all. What you have to understand is that the water itself isn't what's making the power. The water inside the engine is enabling the engine to run a more aggressive tune and it works because we’re making the engine sweat on the inside.
I know this sounds stupid but I’m not making this up. To understand the concept behind water injection inside the engine you have to understand why you sweat? You sweat when you are hot. When you sweat water appears on your skin. As this water evaporates you cool down. You cool down because water has a very high heat of vaporization.
In more simple terms water absorbs massive amounts of energy in the form of heat from its surroundings as it transitions from a liquid to a vapor. This is why if you are much colder when you are wet. Water is taking away massive amounts of heat from your body as it vaporizes and your body struggles to maintain a normal body temperature and you start shivering.
With our nozzle, we are injecting a fine mist of water into the engine. As it vaporizes inside the engine it takes away a massive amount of heat from inside the engine. This is a very good thing because excess heat is the ultimate killer of power and efficiency inside an engine.
Most gasoline engines, especially those with turbo or superchargers, are limited by knock or pre-ignition.
Knock and pre-ignition are NOT the same thing. Pre-ignition occurs before the spark plug fires when the piston is going up. Pre-ignition usually destroys an engine very quickly and it can easily burn a hole through a piston. Knock occurs after the spark plug fires when the piston is going down. Knock can be anything from very mild with minimal damage to very destructive.
Excess heat inside the engine is the main prerequisite for both pre-ignition and knock.
So with ethanol and water in the mix I not only reduced the heat in the chamber but I also increased my resistance to knock and this allowed me to do two things. 1. Increase my boost pressure and 2. Increase my ignition advance.
Increasing boost pressure of course increases power but it also introduces additional heat into the system leading to an increased risk of knock. But I can re-introduce heat into the system because I have taken away a lot of heat with water-ethanol injection.
Increasing ignition advance can also increase power but it too increases pressure and heat in the chamber and leads to an increased risk of knock. It is here that the increased knock resistance of ethanol helps the most.
What I should is that I could have perhaps achieved an even higher power output by running methanol instead of ethanol because methanol has an even richer air-fuel ratio for peak power and an even higher heat of vaporization but methanol is toxic and cannot be legally purchased by individuals in most countries in Europe so I went with ethanol which is very close in performance and isn’t toxic
But wait there’s more. With water ethanol injection I don’t have to worry about carbon buildup inside my engine. The vaporized solution acts sort of like a steam cleaner and keeps things inside the engine carbon deposit-free.
So as you can see water-ethanol injection has many many benefits….so the question is why aren’t cars running this from the factory? Well, the answer is simply because it’s an added cost and complexity but I think that almost every turbocharged car can benefit from a system like this. Many modern cars have small turbocharged engines in the range from 1 to 1.6. liters achieving anywhere from 120 to 300 horsepower. To get this much power these engines have to run pretty high boost pressure. When you put such an engine in stop-and-go traffic in hot weather things get very hot very quickly and I’m sure that if you own such an engine you have experienced how in such conditions these engines are unable to reach anywhere near their advertised fuel efficiency. This is because they only have air and gasoline to work with and when things get hot and they register a little bit of knock they have no other choice but to cool themselves by dumping extra gasoline into the chamber. This means reduced fuel efficiency and reduced power output. Adding water injection alone could improve power and efficiency for these engines.
A special thank you to my patrons:
Daniel
Pepe
Brian Alvarez
Peter Della Flora
Dave Westwood
Joe C
Zwoa Meda Beda
Toma Marini
Cole Philips
00:00 The setup
03:30 Why it works
10:47 Gasoline vs Ethanol
14:54 Tuning
19:57 What really happened at the dyno
#d4a #boostschool