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Anyone tried direct water or even water/metho mix injection before?

Have read in a few tech books that it's a good idea with quite a few advantages for detonation reduction and I reckon would supplement the FMICs nicely, especially on hotter days and on track days. For instance I have a pretty aggressive tune that I might have to back off for summer which sucks, I'd rather help reduce detonation as much as possible and keep the tune for whole year by having water injection.

One book says best to put it at the inlet of the compressor, but didn't say why. Any suggestions as to why?

I reckon the blades would get a hammering if you didn't set it up right.

Would have though after the turbo or after the intercooler would be safer.

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freebaggin,

This sort of stuff is usually reserved for drag cars and race cars. I think most of the injection is done into the intake manifold, to reduce the intake air temperature.

I would think that there are many other things that can be done before you need to resort to this, but if you want to then speak to someone who has set it up in a race car before.

See'ya:burnout:

Cant understand why you would put it into the intake of the compressor, it would get compressed and heat up. Also injection before the intercooler would have very little effect, the best place would be after the coola, usually either the plenum or directly into the manifold runners.

As GTS-t VSPEC says, it is usually associated with high output drag cars. To qote Corky Bell (us high performance guru) "Water injection is best used when no intercooler is preset. Do not allow a situation where the water injector is used as an excuse for improper air/fuel ratios. All things considered you are better off never to have heard of water injection." He further describes water injection as 'an inherently unreliable device whos time has long since passed.'

If you are after a fix for summer driving you could try using an octane booster and getting a retune, or try using heat wrap and/or ceramic coating on manifold and coola pipes to keep underbonnet temps down, as well as ensuring a good airflow to your coola.

Just my 0.02

Steve

EDIT: another thing you could try, although I am not sure about the legality in australia, is using an evaporative gas like nitrogen, sprayed at the coola. Good for short periods when you are in the mood for getting serious.

The reason it is put on the compressor side is so it atomises better. The problem is it wears your blades out over a period of time.

When using methonol you need to be very careful of hydro lock as it is a very dry type of liquid, no lubrication properties what so ever. A way to get around this is to spray some WD40 into the methonlol/water reservoir.

Using methonol is illegal for this purpose as it is a carcinogenic, but ethonol can be used in its replacement.

WDracing runs an alchohol injection kit on his R32, he uses isopropyl as opposed to methanol.

A good kit can allow you to run several more psi without detonation. WDracing has run 28psi on the stock block, ecu and fuel system (to4E) a number of times and regularly at over 20psi.

Read here:

http://forums.skylinesdownunder.co.nz/show...y=&pagenumber=2

A few mixed opinions but all good stuff, thanks.

Have been searching on the net and heaps of info. MRT for example has a kit from Aquamist and I'll call them tomorrow to discuss the benefits and also to see if it can be controlled by my LT-12 ECU, etc.

Would want it to be triggered by two inputs, firstly by inlet temp (say only over 30°C) and the secondary trigger might be above 0.5 Bar. Probably stick to water only I think, have a large supply of high purity deinonised water at work that would be good.

Just gotta work out myself if it's worth the hassle I spose.

The reason for spraying it before the compressor is that you can use boost pressure as the driving force. If you spray it after the compressor, then you need a pump capable of overcoming boost pressure - remember, fluids move from hi-pressure areas to lo-pressure areas.

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