Cold Start Valve for Water Injection?
 

Just recently acquired a 1985 VW Jetta GLI. Physically it's in extremely decent shape (just moved to California. 85 cars sure aren't usually like this back east).

The cis-e needs to be tuned. It's currently not really all too driveable.

That said, once (if) I get everything all set and good, I'd be wanting to look at ways to improve economy and power. Since I'm going to be sticking with cis-e most likely (this is my first), it may be a little interesting. Hopefully I'll be able to go without the cold start valve.

So that got me to thinking.. how good would the csv be at spraying water? What if I got a standalone pump and water tank, and regulated the csv somehow so it sprayed an appropriate amount of water? It should be designed to evenly spread among the cylinders.

So then I could advance timing even more, while on 87 octane. Specs call for 6'btdc, and people say they can run 10'btdc on a stock engine on 87oct. So how much is too much? When do gains stop?

It is cis-e though, so it does read the o2 sensor. I'd rather not have to remove the dpr though since I'm sure sometimes extra fuel would be desired. Any way to run lean with water and not have the dpr go crazy trying to compensate?

And about timing, is manual adjustment necessary if there's a knock sensor? Or will it automatically just keep bumping it if possible?

Cool! Anyone try something like this? Or want to? :) It'll probably be a while before I can get the car restored enough to be a main driver.

the only time the CSI is used is at cold start. in cali, you probably won't even notice it's loss. My cressida doesn't notice its lack till under 40*f.

a few concerns:
-just water will corrode/rust the CSI. tap water will clog it with deposits.
-are you planning on using it all the time or just occasionally? the CSI is sized for a very rich delivery, probably more water than is good for constant running and it'll drain your supply pretty fast.
-the CSI is intended for fuel injection pressures... 30-50 psi (I don't know what your car will run specifically) and you'll need a pump to put that much out or it'll just sort of dribble out instead of spraying.

Gasoline is so much lighter than water. I wonder how it would even spray out of the CSI.

Might be something to test before trying it.