xr4tic

I got the WI installed sunday, and after making sure it was working, I went to the drag strip.
Unfortunately, it was my first time with my A4, and my launches were terrible.

I did some datalogging with the VAG-COM of RPM, Timing, and Intake Temp (after the Throttle Body)

All these runs were done one after another, I didn't even shut the car off between runs.

Car setup: look at sig. The lightweight flywheel was really hard to launch, and I never went into 4th gear because of the taller 2.8 gears. I'm positive with more power, the taller gears would be helpful since I can hit 100+ in 3rd.

FWIW, my best run was 15.485 @ 88.22, 2.341 60', and I hit the rev limiter in first in that run (my tach can't keep up with the motor) I made 4 more runs after these 4, but it was after letting the car cool down for a while, all with the WI on, and the outside temps dropped as well (low 70s - high 60s).

Looking at the graphs, you can see the intake temps were as much as 50 degrees cooler, and ran on average 6 degrees more timing. I seriously need a race chip. I also think I'm injecting too much water, or injecting it too soon. I'm going to play with the jet sizes and boost set point.

Run 1:
5:20p, 80 deg F, WI off. Straight off the street, car was hot, bogged it off the line.
16.236@86.36 - 2.707 60 foot
<img src="http://pictureposter.audiworld.com/12130/run1.jpg">

Run 2:
5:33p, 80 deg F, WI off. Car still hot, slight bog (but my best 60 foot of the day)
15.754@86.52 - 2.297 60 foot
<img src="http://pictureposter.audiworld.com/12130/run2.jpg">

Run 3:
6:04p, 80 deg F, WI on. Car still hot, decent launch, but hit the rev limiter in first, and missed 3rd gear.
16.056@86.31 - 2.428 60 foot
<img src="http://pictureposter.audiworld.com/12130/run3.jpg">

Run4:
6:26p, 80 deg F, WI on. Car still hot, I gained 1 mph over the non-WI runs, but it felt like it bogged going into second, and I shifted into 3rd earlier.
16.095@87.54 - 2.510 60 foot
<img src="http://pictureposter.audiworld.com/12130/run4.jpg">


So in summary, it works, but I can't drive worth a damn

Pat-SoCal

But it doesn't look like it was worth the effort.

CharlieGSanD

this is shooting water int the combustion chamber, right?

is this the one on europeanspeed, or the aquamist system?
what size nozzzles are you using?

you can really see how the intake temps went down with the increase in rpms

looks promising, keep us updated!

J. Daniel

Your lack of experience running the 1/4 makes it difficult to assess the value of the WI, but with the WI allowing much more advance it's got to be faster.
As a side note, I'd bet you'd be much faster if you were to shift closer to 6000 RPM than 7000.
Thanks for posting the plots.

xr4tic

It definately needs some fine tuning, so I'll save the final verdict until then. I don't have that much invested so far.

It offers the same benefits as a larger IC and race gas, but at a fraction of the cost. A race chip with more timing is definately needed for the full benefits.

xr4tic

since the car is running for longer than 15 seconds.

As for the shift points, I'm not sure. 1st gear should be taken to 7K. 2nd needs some experimentation. I think the lightweight flywheel and cooler intake temps will help extend the power band. I think around 6500 might be the optimum point.

Bollinger

BTW, pulling tractors (as in tractor pulls) all run water injection.

Could you explain the timing numbers. Are you saying that -20 is less retard than -14? Why is that, are the measurements degrees after TDC or something? 20 degrees before TDC seems like a lot of advance, too much actually.

Does it feel any different? How much water do you inject, either in ccs or as a ratio to gas? Do you change the water amount based on fuel flow or revs or something or is there just on and off.

I have to agree with Pat SoCal, I think that the system is currently demonstrating that is is generally easier to mess things up and make them better. Until you get the amount of water to be closer to correct you probably won't see much real benefit or even some power loss.

Evzen

This is direct WI into intake after turbo? or is external WI on intercooler?

Bollinger

Because first of all that is very complex and would require difficult modifications. Second of all this mod lowers intake temps (as measured on the graph), and it can't do that unless the water is injected into the intake.

xr4tic

I looked at the Spearco system for $200, but have been told by numerous people it was junk.
I looked at the Aquamist system, which is very nice, but at a cost of $450. I didn't want to spend that much and find out it didn't work.

My system consists of:
Pump - 1.4gpm @ 60 psi - $60
Solenoid - $30
Aquamist Nozzles - $16 each
Hobbs pressure switch - $30
Misc fittings/lines - $15
Special tap for the nozzles - $20

So I have less than $200 into the system.

Right now I have a 0.7mm nozzle mounted 3" from the TB, and I just tapped into the headlight washer line to feed the pump. I use washer fluid that has Methyl Alchohol in it The water starts injecting at 4 psi.

I'm planning on adding a small nozzle at the turbo outlet, and then reducing the size of the one near the TB. A nozzle at the turbo will reduce the temps going through the IC, and a nozzle at the TB lets some water get into the combustion chamber to help with detonation. I've got a 0.5mm and 0.6mm nozzles that I'm going to try. I might also try raising the boost set point.

I'll have a write-up when it's sorted out.