Anybody use water injection?
 

I want to know any real-world dyno numbers on water/alky injection and where it was injected (pre- or post- blower). Previous injection threads do not list dyno numbers on Eaton-blown cars.

Depends on what you're after. If it's the intercooling effect, pre-blower is ideal. But be warned, it's very easy to inject too much. I'm running a fairly small nozzle, and had problems last summer with it. Spring will be bring a 50/50 water/methanol mix, to hopefully solve that problem.

Read my sig ;) This is my 4th system in this car alone. All home-built, but I do have a bit of experience and knowledge with other applications. A friend at work has an Aquamist 2D system on his VW Jetta with a Neuspeed SC conversion (Eaton M45.....cute little bugger). He's a member here as well because of the Eaton commonality. Greyhare is the name.

There are a lot of write ups about it on ClubGP if you want some more info. It seems a lot of people are experimenting with it lately.

http://www.waterinjection.info/

The forum will be started up again soon. I'm a member there.

H2O/Alky injection is not going to make any power by itself. It will allow you to run a setup that you couldn't run on pumped gas tho. You have to think of it as Race Gas on demand.

Not necessarily true. It has the effect of raising the oxygen charge density, cooling the intake charge, and keeping the internals clean. All increase power, particularly on forced-induction motors.

The physics behind why it works in all these ways is complicated. Combustion is not an easy science to understand when you start talking about h20 injection. The reason our bombers over Europe in WWII could fly higher than the Germans out to get them was stricltly because the mechanically-supercharged (gear-driven SC's) engines on the B-24 and B-17 aircraft were water-injected. Think about that for a minute.

ok i gotta know... ive heard that injecting water b4 a turbo will destroy the turbo.... does it have the same effect on a roots supercharger

No. The SC doesn't turn at the high rpm's the turbo does, and the vanes are much more substantial. There's actually a benefit to the SC application, as the water keeps the rotors clean, where on a turbo, you can't do that.

The other problem is that in a turbo application, injecting post-turbo requires ALOT of pressure and an expensive pump.

Here is an Excel spreadsheet with initial data.
I need to go up in nozzle size and set it to turn on sooner but, it does make a differance.
Spinning the blower at 14152 rpm on top of 10:1 stactic CR; I need all the help I can get.
The water is injected after the rotors. (little blue hose in sig.)

http://home.comcast.net/~vw20sc/pics...03-045-xxx.xls

Looks like it helped a bit with the KR. Can't wait to get mine going with the 50% methanol mix this spring.