Water Injection...anybody running that?

[S14Drift!]

I have bought a Aquamist water injedction system from http://www.aquamist.co.uk

I got the 2D system http://www.aquamist.co.uk/cp/806-009/806-009.html

I wanted to know who's using this on a RB...idealy a RB26DETT, I would like to know your result...and how it affect the power or knock level.

[GTRgeoff]

I have mine running with a super fine mist nozzle post intercooler. It is throttle position activated and runs off one of the wiper motors. As i only had detonation near full throttle I didn't see a need for anything more complex. It allowed me to start to run 12psi with my modified (stock) turbo when previously I was stuck with 9. Unfortunately I didn't have it on in time to save 2 broken pistons incurred when playing tag with a porsche turbo on a hot day. Had the FMIC water spray on but when I pulled in tight into his slipstream at about 170kmh at full throttle I had a little detonation and now about $3K later I nearly have the rebuild finished.

[meshmesh]

geoff,

not sure that what you've got is "real" water injection. I thought water injection is a mist spray of water directly into the manifold. I have a mate running this on his car, he's running ~35-40psi from his 1000hp garret turbo. He swears by it.

[4 Doorz]

wouldn't that just cause a 'hydraulic' as the water wouldn't compress in the compression stroke and your engine would just explore?

[strutto]

The water should be a fine mist and therefore be evaporated easily thereby reducing the temps in the combustion chamber and preventing detonation...

[nicknick]

i would love to find out more about this and how much it costs

[meshmesh]

i would love to find out more about this and how much it costs

my mate rekons around $400-500.

[RBVS]

methonole would be better than water i would think, ive herd of good things from running a good set up. large boost realy low temps.

[FATGTS-R]

Many people run a 50/50 methylated spirits/water mix.

[Busky2k]

You dont want to run too much methanol because it'll screw with the AFRs. Also straight methanol is corrosive to aluminium and most pumps are not compatible with it!

[nicknick]

MRT performance in ryde has he set up for $1050 fully installed, thats for the basic set up, and it goes up from there if you want full mapping capabilities.

[GTRgeoff]

geoff,

not sure that what you've got is "real" water injection. I thought water injection is a mist spray of water directly into the manifold. I have a mate running this on his car, he's running ~35-40psi from his 1000hp garret turbo. He swears by it.

Real water injection is atomised water injected into the air stream and entering the combustion chambers. I could give you a post-graduate engineering dissertation on the cause and effect of atomised water and the suppression of detonation, but since you didn't read my post I won't waste my effort.

There are plenty of threads on here with equally qualified/experienced individuals who have discussed it at length. Some actual users and designer/builder of their systems... not mates of. Try a search.

Cost would be less than $100 (Yes $100) for a suitable setup if you did it yourself. Anything more is an absolute ripoff (sorry S14Drift!)

I have applied it to 2 cars thus far, one of which was a Lynx with oxygen injection at 60 psi into the free air stream (chemical supercharging), extra injector and water injection to supress detonation and it managed 7s 0-100kmh down from 10s.

My underlying point though was if you tune too close to the limit, even with protection systems, prepare to spend money rebuilding. In my case new forged pistons, GTR rods and fuel pump, balance and a few extras as well as a PFC for even more tuning margin.

[meshmesh]

Gee's geoff, you gotta take a chill pill & relax,

Now I'm not sure that you read my post correctly,

not sure & I thought

Those 4 words, should tell you I dont have a post graduate in water injection. As I said, I thought that water injection is directly sprayed into the manifold. I did a search some time ago, & all I got was "intercooler spray" type threads, obviously were nozzles spray water directly onto the coolers.

Now you've just gone & confused the sh!t out me. No hard feeling

[GTRgeoff]

Hell sorry man....I just spent the morning arguing with people about explosive ords safety compliance and they were not listening and then i bite your head off for no reason. I apologise.

I run both FMIC water spray and water injection using the spraying systems water atomiser nozzles. The spray is so fine that it almost won't reach the ground on a warm day.

As i said it is post intercooler and I do this because I don't want it to settle out in the cooler, but it is on a rising pipe so if it decides to fail and continue running at idle it will run down to the cooler. The smaller pipe maintains a higher velocity that doesn't allow time to settle on the way to the plenum.

You can put it in at the plenum but doesn't (may not) allow sufficient mixing in my view.

Really it doesn't have to be too complex and the price of some of these systems is an absolute rort.

My problem was the lack of airflow over the cooler even with the water spray probably brought on the detonation but had I had water injection at the time I would have maybe prevented the detonation. Too late now though

[nicknick]

just wanted to and my 5 cents, i spoke to a few places in sydeny about the water injection kit, and most places said it was a waste of time unless your running 30psi, cause if its not pinging already whats the point, and i also asked them what about on hot days when you boost your car, and they said to me plain and simply, DONT BOOST ON HOT DAYS, which was pretty staight forward, so i think ill stick to that advise and keep a 1000 bucks inmy pocket for nos

[GTRgeoff]

unfortunately I don't have a choice of the weather when I race (only sprints) so the added advantage is too great to ignore.

Sounds like a crap workshop if they think you HAVE to run 30 psi to make it worthwile.

As with everything I think the main advice would be IT DEPENDS.....

[nicknick]

hey skylinegeoff, i dont want to sound negative but it wasnt just the one workshop brother, most of them that i asked. sory man i dont know much about them but that is what i was told.

[GTRgeoff]

Truth be told, the only way you will find out is to try it. Then you can laugh in their faces. I'll bet most have never tried a cheap and cheerful approach.

A fully mapped system is something again but I fail to see the value of over $1K unless say you had done enough to boost to 30+psi, so it depends really. At least you can run it on the road, legally, unlike NOS.

Whenever I install something new I always attempt to quantify the result, so I know I'm not BS'ing later. With the intercooler water spray, on a 37 deg day I achieved an average of 17 deg lower intake temp after the intercooler AND an average of 30 seconds to drop the temp off boost to 28 degrees where the temp hovered about 38-42 degrees without and jumped to over 60 on boost at 9psi.

While my temp probe is not located to gather post water injection temps the reality was an increase to 11psi at the same ignition advance (I don't remember how much I had that time, about 14 deg) which equates to a nice little power jump for next to nothing.

Now I have installed an 800hp FMIC I'll continue to analyze the value of water spray/injection.

Try it and see is all I can say. Check out Autospeed for their views and articles. The water spray I use is the spraying systems one from their DIT IC water spray article, about $40 for all the bits.

[meshmesh]

geoff,

how much difference do you think there'd be if you sprayed directly into the manifold? compared to what you've done.

[GTRgeoff]

I would suggest you would require one injector per runner in the manifold for equal delivery, and you could result in over delivery of water and run the risk of water buildup if you had a fault, resulting in hydrostatic lock and broken bits next time you start up.

Mine is plumbed into the pipe running up from the intercooler, before the crossover pipe which should give sufficient time for 'mixing' before the throttle and plenum.

Once installed you just keep an eye on water levels. With the IC spray and the injection it used about half of the std R33 windscreen wiper res per week. Each operated off a different motor and control circuit.