water injection

[VN_Luke]

Hey just wondering if anyone has any experience with water injection with a side mounted roots blower?

- Optimal placement of water injection?
- expected effects (how much intake temp drop?)
- potential damage to rotor coating?

etc?

just general information would be appraciated..

and also how much more timing can be run with said water injection (as a rough guide) ?

Luke.

[WILD VR CLUBBY]

i would like to know where the water injection hooks up to is it into the cylinder or in the intake manifold

[simc]

I did a quick google search, a heap of info.

Here is one fella thatknocked one up pretty cheaply.
http://www.dawesdevices.com/howto.html

[VN_Luke]

setup's all done already

I used two fuel injectors with a makeshift 'fuel' rail (filled with water @ around 45 psi), wired into the car's remaining injectors and through a hobbs pressure switch so they flick on at boost.

works a treat

[simc]

LOL.. damm ur quick!!

Where did you get the 45psi from? fuel pump?

Power increase?

Get some alcohol in there man

[vn6pwr]

Originally Posted by simc

Get some alcohol in there man

That would defeat the whole purpose of cooling effect of the water

My dad used to run water injection on his old Dato 200B and from what i heard it had never went better

[VN_Luke]

45 psi comes from high pressure water pump with an inbuilt pressure switch (so no return needed!)

i'd guesstimate and say i can run approx 5 degrees more timing advance with the water injection without pinging

i haven't done a comparison of intake temps before/after yet!

[Matt_vp]

Any pics of your water injection setup?

[shamus]

Originally Posted by vn6pwr

That would defeat the whole purpose of cooling effect of the water

alcohol will have a better cooling effect than water......won't it?

[immortality]

i've heard a 50/50 mix off water & alcohol works real good, water cools the intake charge and steam cleans the engine (hehehe) the alcohol has the same effect of increasing the octane rating of the intake charge. the combination alcohol/water injection i've sen a few time on turbo cars. one chap i talked to suggested that injecting the mixture directly onto the impeller is the best way to atomise the mixture. this was based on a centrifugal supercharger setup however

[VT-565]

Originally Posted by immortality

i've heard a 50/50 mix off water & alcohol works real good, water cools the intake charge and steam cleans the engine (hehehe) the alcohol has the same effect of increasing the octane rating of the intake charge.

Water/alcohol mix is good, but the alcohol is not in there as a true octane booster, the alcohol evaporates at a lower temperature than water, in turn, it removes more heat from the intake charge on atomisation.

Originally Posted by immortality

the combination alcohol/water injection i've sen a few time on turbo cars. one chap i talked to suggested that injecting the mixture directly onto the impeller is the best way to atomise the mixture. this was based on a centrifugal supercharger setup however

never aim an injection nozzle at a centrifugal compressor. will cut it to pieces, water is an effective cutting medium at high velocities and this is asking for trouble. ever seen steel barrels cut open with high pressure water jets? very effective. however, if you ensure the mix is well atomised, there is nothing stopping you from placing the nozzle way before the compressor. but most effective position is post-compressor.

[immortality]

Originally Posted by EcotecManiac

Water/alcohol mix is good, but the alcohol is not in there as a true octane booster, the alcohol evaporates at a lower temperature than water, in turn, it removes more heat from the intake charge on atomisation. never aim an injection nozzle at a centrifugal compressor. will cut it to pieces, water is an effective cutting medium at high velocities and this is asking for trouble. ever seen steel barrels cut open with high pressure water jets? very effective. however, if you ensure the mix is well atomised, there is nothing stopping you from placing the nozzle way before the compressor. but most effective position is post-compressor.

this guy i talked to had used this setup so it must offworked. don't know about the pressure he was using but from memory he ws using nitrous nozzles and jets to regulate the amount of water/alcohol that was going in.