14psi on 4agze

[Duk]

You guys are missing the point!

Water methanol does NOT have to be proportional to fuel supply! The research indicates amounts of water meth in concentrations from 10% to 150% being effective. My point is that this is one of the most forgiving things to tune full stop!

If you want to make it complicated for kicks and giggles go ahead!

Using a hobbs switch to engage water meth at 10psi or greater if wished will ensure you are already at wide open throttle and pretty much maximum fuel flow while water meth is being requested anyhow. This makes the need for 'proportional' flow pretty much redundant. Oh and also cures the problem of rusty efi style injectors because you can use anything from mechanical alky injectors (old school stuff) to garden misters to introduce the stuff in the air intake pipe in front of the supercharger!

Every engine is going to prefer it's particular water/fuel ratio.
I bought a book from a guy who does a supercharger kit for another breed of car I'm into. His research into water injection had him going thru heaps of old NACA world war 2 engine development stuff for supercharged bomber and fighter aircraft.
Long story short, water injection is a hugely effective detonation supressant etc, but there are desirable water/fuel ratios that give the best detonation protection for minimum water consumption.
The best WW2 water injection systems were also variable flow.
Excess water will reduce torque/power.
I see your point of full throttle, 10psi switch on, but full throttle 10psi at low revs will require less water than full throttle 10psi at high revs.
You are also potentially missing out on valuable lower rpm torque if you can use it at lower boost levels.
Done with more attention, I think a well set up water injection system could add lots of driving enjoyment that isn't only measured at full throttle on the dyno.
Some smarts, research and imagination should have a system in place for reasonable dollars, too.

[NME308]

Hey Plonka and MWP I'm not trying to argue with you guys about the fact that water meth can be done HEAPS better than I am doing it or that there would of course be benefits to tuning it like an efi style system!

All I'm saying is it can be done extreme povo for excellent results - like keeping a stressed engine together.

MWP I like the sound of your proposed setup. Keep us informed if you go ahead with this stuff!

Guys there may well be merit in the writings here and there regarding using distilled water. I use tap water mixed 50/50 with methanol, and I have to thoroughly clean the inline filter on a regular basis as it grows a fungus or something which quickly restricts the filter. The tank also gets quite a large level of scum floating around in the mixture after a couple of days, it looks like you filled it with flood water! This is not a problem to me as I use the system once every couple of months on race day. For a daily driver tuned to rely on it this could be troublesome to say the least!

Cheers,
Jason

[TERRA Operative]

Daily use should prevent the water from stagnating, and the constant refilling should keep the system sufficiently flushed through to prevent too much buildup.

[NME308]

Daily use should prevent the water from stagnating, and the constant refilling should keep the system sufficiently flushed through to prevent too much buildup.

Please do not throw mud in the water here no pun intended.

For someone seeking to use water meth on a daily driver like MWP's suggestion and expecting the system to be as reliable as their efi your advise will result in pain. All the manufacturers of professional kits advise only distilled water for this reason - tap water contains many impurities which over time will clog lines and nozzles. Google it for yourself if you don't believe someone like myself who actually uses water meth!

As I mentioned earlier I clean my system after each race day therefore tap water is no problem to myself... Oh, and did I mention in previous posts and above I ACTUALLY RUN AND USE A WATER METHANOL INJECTION SYSTEM ON A REAL CAR WITH A REAL ENGINE!


Keyboard warriors...

[Duk]

Adding a decent capacity water filter would help http://autospeed.com/cms/A_110368/article.html.

[TERRA Operative]

Without heating the water, those impurities should cause no problem, if flushed through regularly.

The same principal applies to your kettle and taps in your house. Kettle gets buildup, cold tap does not.


When was the last time you had a problem with scale or slime buildup in your window washer bottle? If it needs to be cleaned every few months, then so be it. You don't expect your engine to run indefinitely without maintenance, this system is no different.

I'm not saying that distilled water isn't a good idea, just that tap water isn't going to cause massive problems outside of a decent maintenance schedule.

[MWP]

I'm not saying that distilled water isn't a good idea, just that tap water isn't going to cause massive problems outside of a decent maintenance schedule.

Agreed, with a decent filter, there should be no reason why the nozzle would get clogged up.
Even if it does, surely itll be over years of use, not weeks/months. I can handle replacing the nozzle every year or so if need be.
There is no way lines should clog up, or even build up a scum if there is a little alcohol mixed with the water.