Water Injection
Moderator: Team
Water Injection
I have heard of guys using water injection on different applications before. Mainly seem to hear about it from the turbo guys. Can someone explain to me what water injection does and how it helps the motor? I always though water in a combustion chamber was bad news. Thanks, Todd
Water injection is most often used in Turbo application, where the increased cylinder pressure and temps are too much and the motor detinates. To help detination you need to lower inlet temp i.e. better intercooler, lower compression, slow up timing, or better fuel etc. etc. Injecting water, lowers the combustion temps and helps with detination. It is sort of a crutch. Normal aspirated engines, you would not want water displacing fuel and air, but with the supercharging affect of a turbo it is a good trade off. Hope that helps some.
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Torquemonster
basically agree with the above post
on a n/a engine it can be a great economy device - it allows much leaner mix and more spark... but this is the wrong forum for that... lol
Ok - water injection differs from Intercooling in that it offers direct IN-CYLINDER cooling. The trick is to MAP the flow and ATOMIZE it. To atomize water properly you need at LEAST 100psi - preferably more - and a good jet or 4.
It can add substantial power both directly and indirectly - most will never get beyond the small gains. There's a science in there and few know it... but you will not see ANY World Series Rally cars without it - and those are very high tech cars.
I've used water to run 9:1 at 18psi boost on 91 octane with 24 degrees timing at full boost - as a SAFE tune for any conditions. Try that without water.
On a limited octane non intercooled blown drag car - you should see 7-8mph with water - not such a bad crutch is it?
Run methanol mix for best results. Some of course inject much more methanol and use it as a fuel power adder - but this complicates the tune. I prefer up to a 40/60 mix of water to methanol rather than a 100% methanol mix.
To avoid blocked jets on water - use distilled water.
ERL make the most sophisticated units - Aquamist - available from the UK but they have USA distributors
Snows Performance make a much cheaper setup that is not 3D mapped but offers the needed 100+psi etc - its good value.
If you run a race gas with sufficient octane for max power tune and the intake temps and EGT's are fine - you do not need water. Water is needed when cylinder temps are high or when octane is low.
on a n/a engine it can be a great economy device - it allows much leaner mix and more spark... but this is the wrong forum for that... lol
Ok - water injection differs from Intercooling in that it offers direct IN-CYLINDER cooling. The trick is to MAP the flow and ATOMIZE it. To atomize water properly you need at LEAST 100psi - preferably more - and a good jet or 4.
It can add substantial power both directly and indirectly - most will never get beyond the small gains. There's a science in there and few know it... but you will not see ANY World Series Rally cars without it - and those are very high tech cars.
I've used water to run 9:1 at 18psi boost on 91 octane with 24 degrees timing at full boost - as a SAFE tune for any conditions. Try that without water.
On a limited octane non intercooled blown drag car - you should see 7-8mph with water - not such a bad crutch is it?
Run methanol mix for best results. Some of course inject much more methanol and use it as a fuel power adder - but this complicates the tune. I prefer up to a 40/60 mix of water to methanol rather than a 100% methanol mix.
To avoid blocked jets on water - use distilled water.
ERL make the most sophisticated units - Aquamist - available from the UK but they have USA distributors
Snows Performance make a much cheaper setup that is not 3D mapped but offers the needed 100+psi etc - its good value.
If you run a race gas with sufficient octane for max power tune and the intake temps and EGT's are fine - you do not need water. Water is needed when cylinder temps are high or when octane is low.
