Re: The myth of the 100 mpg carb
As CB stated, it generally is used to reduce/eliminate detonation. It does add oxygen to the mix; so theoretically, should help power and mileage.
Had a friend that installed one. The water reservoir was sufficiently small, it probably was out of water as much as having water. Couldn't tell any different with/without; but I had modified the carburetor specifically for the tune of his engine.
Oldsmobile had an alcohol/water injection system on the Jetfire (turbo) to eliminate detonation. It was so successful that Ford used a boost sensor and distributor retard on the turbo Mustangs.
Would guess water injection would be more successful on some appliations than others. Like I stated earlier, we couldn't tell any difference on my friend's car.
For best results with a carbureted car/truck engine; picking a carburetor that is sized correctly to the engine and calibrating accordingly would be my suggestion. And while I generally favor Carter/Rochester/Stromberg, not going to argue brands. The skill of the tuner is equally important to the brand of carburetor.
Jon.
If you truly believe one size fits all, try walking a mile in your spouse's shoes!
Owner, The Carburetor Shop in Missouri