You guys are missing out on alot of power by simply running straight water.

Doesn't matter if you run meth or alchy you will see better returns using them as and octane booster and chemical intercooler.

I've even gone as far to try 50/50 blend of H20 with either and it causes the car to run richer with less get up and go.

I saw my best knock free performance from 11:1 AFR, 26psi, and aggressive timing. You should be able to run nearly 10* at peak torque when spraying 100% alchy.

 

low afr/rich mixture needs more timing due to the slower combustion

when you approach 12.5afr - combustion is quickest, you dont need/need less timing

it is not the amount of fuel you introduce into the combustion chamber, you want the quickest bang at the right time to push the piston down to make power

water rich injection in a rich/cold combustion will result in "less get up and go"

 

good read

https://www.evolutionm.net/forums/sh...45&postcount=4

 

Another very good read by SlowCar. The variable that keeps getting left out of the equation is what is the ideal timing curve for running pure water with "very high boost and lean fuel ratio"?

I ask this because timing effects the EGT sensor drastically, not neccessarly the in cylinder temperature. What I am saying is that if the timing is too low the EGT sensor will read very high due to excessive fuel being burnt in the exhaust manifold where the EGT sensor is located.

How can you determine the best timing curve to start with before adding more boost and leaning the fuel out?

 

there is very good info that Richard has provided scattered all over this forum, i'm just copying/pasting them thats all

 

Yeah, I know. I have read most of them already.

Have anything on timing? I haven't seen one specifically call that one out yet (VIII in particular would be good )

 

good info guys.
subscribed...

 

DC, remember that flow rate is based on injector duty. If the duty cycle is fifty percent then that is approximately the percentage of the max water.

with cams you may be hitting 75% duty on those injectors, dropping back around 60% most of the time.(?) maybe more, or less, I am guessing.

I too am injecting straight water, with the .8 nozzle. That is until tonight when I added a .6 nozzle . The .8 is about six inches before the throttle body, the .6 is right after the intercooler.

With just the .8 I have my afr in the mid twelves +,- and switch between 20 or 23 psi.

With the .6 added to the air charge I got noticeable bogging around 5000 rpm.
So right now I need to determine if the spark plug needs regapping or if there is just to much water.

 

Keep us posted. I've been wondering what to start with on the nozzle size for straight water. I'm almost done with my install.

 

^^^ Straight water will probably cost you power unless you really crank the boost. But if you plan on sticking with water than you'll need a very small nozzle. I'd suggest something in the 3-4GPH range.

 

well I was so disappointed that my car was bogging I looked for smaller jets and not finding any, decided to change the plugs, hoping that was the problem instead.
To no avail, still bogged down, then I realized I was flowing more water than before so my over flow limit was being hit, my car was reverting to low boost because the system thought I had sprung a leak.
I adjusted the limit screw and off I went. neato all is well with the world.


So I guess my comment about to much water is all wet.