Technical Vintage Water Injection - need info

You know the normal logic, if a little is good a lot has to be better. Funny how often that turns out to be wrong.

 

The simplest I've come across was water fed from a bottle into the vacuum advance vacuum line via a hypodermic needle.

 

The problem with p***ively feeding into a vacuum line is that water will be ****ed in the most at high vacuum (low load) conditions, and not at all at full throttle, no vacuum conditions.
Having the water enter just above the throttle plate would be much better.

For pumped systems, I prefer this piece:



They're really expensive new, but can be found on the auction site for one or two C-notes if you are diligent. 12 volt units are harder to find though, most seem to be 24-36V.
100 psi, no problem dead heading as the motor is pretty smart and only powers the pump to meet demand.
1/8" NPT ports.