i have used water injection on my propane fuelled hemi 6 for years(swear by it)basically it allows you to run higher comp ratios before the start of detonation(pinging).with propane(102-105 octane)12:1 is about the highest you can go but with the water 14:1 is possible,similary with petrol(gas)10.5:1 is about it(98octane) water allows you to go to 11.5.there are 2 ways to iject the water.one is by a small pump(mainly used on turbo's) and the other is by vacume such as i use.uses about 1/2 a liter per 75 liters of fuel(depending on driving conditions,the harder you drive the more water that is used)steve
