Water injection and water methanol injection (wasser methanol einspritzung) are nothing new, in reality water injection dates again to world war II, when fighter aircraft and heavy bombers considered necessary more power to get off of fast and frequently unimproved runways. Engineers in the day learned that by injecting water into the combustion chamber, cooler combustion temperatures led to more engine performance, and allowed lower-Octane fuels, more compression ratios, or perhaps more power to be utilized. Even more, this technique didn't have an effect on the durability of engine parts, and really led to cleaner combustion chamber elements like piston tops and valves. Over time, water injection was adapted to aircraft turbine engines, but wasn't popularized for automotive purposes. Some of the water injection (wassereinspritzung) benefits include:
1) More Power: the air cooling properties of the methanol and water and the high octane properties of methanol, help water/methanol systems produce more power. Additionally, the cooler consumption temperatures allow you to run more aggressive timing and/or increase (compelled induction applications) without increasing the possibility of detonation.
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