Seems like we are pretty much on the same page, its great learning new things though.

 

I agree! WI FTW!

 

Can you run 100% tap water? or does it have to be distilled water?

 

NO! distilled water is barely good enough. I ran just distilled and clacium still built up in my pump so I had to clean it all up. ONLY distilled and make sure its a quality brand you can trust.

 

I do not know about all of the other "tuners" that work within the Evo community, but I am willing to bet that most have never pushed 100% WI setup.... I wonder if they know how?

....Sorry about that, its just a little bit irritating that there is such a lack of knowledge in this industry.

Needless to say, I have been there, and while it does not take anymore "skill" it takes the understanding of what your attempting to do.

A Stoichiometric A/F ratio for a given fuel or a Lambda Value of 1.0 should produce the highest Theoretical flame temperature. In lay mans terms, at that ratio of Air to Fuel, the combustion temperature should be the hottest. So when people say running lean is hot, its a matter of perspective. If you are leaner or richer than the Stoichiometric A/F ratio for a fuel, your combustion temperatures will be lower that the maximum. This brings about the question of... If thats the case why don't we run leaner than stoich? The answer is basically two things. The first is thermal management, and the second is a power production window. But we wont really head into that discussion. But for the time being, let it be said that an engine will make the same amount of power with a wide range of A/F ratios as long as the combustion is regular, meaning no detonation, knock, preignition, what have you.

We typically run turbo engines richer than stoich, and with evo's in particular on pump gas, 91-94 octane, somewhere in the region of 11.0:1 to 12.0:1 determined by many factors. If we begin to take fuel away, combustion temperature begin to rise due to less mass of fuel removing heat. The result typically is the onset of irregular combustion (detonation, etc.). If we inject water, we can quench this irregular combustion. To little, and irregular combustion continues due to excessive temperatures, to much and you effectively "bog" the engine. The key is to replace the fuel taken away with an appropriate amount of H2O that will quench detonation. As you AFRs approach Stoich, not only are you running a more efficient AFR, but you are also injecting a volume of water that takes up space and effectively raises your dynamic compression ratio. You can now run much closer or at MBT.

Here's the kicker, lets say your at peak torque and you have a 100% Water Injection setup running 14.2:1 AFR and you run out of water. BOOM... or a little bit slower than that. All of your cooling is gone, your engine is detonating and the combustion temps are pretty much as high as they can get . Blown engine time! Its actually one of those "your heart drops" moments.... I have been there on an engine dyno, calibrating an engine near peak torque, and run out of water. Luckily in my case I had a buddy next to me that noticed the "O Crap were out of water light" while I had my face buried in my computer punching numbers and watching the Torque output on the dyno screen.

Good luck Guys!

 

^^^^ VERY WELL PUT!

Agreed...

Evan

 

Whats anyone else say about the "value craft" windshield washer solution?....good enough to use on a regular basis for those of us without ready access to meth?

 

the thing you want to keep in mind with anything you inject, is its likelihood of clogging the injector. That could come from sediments or scale, tap water from the Southwest comes to mind. Even here in the Northwest I use distilled water to keep mineralized water to a minimum.

So look at the contents, will it leave a residue that will dry and clog?

If you are willing to dismantle and clean your injector often then your problem is less.