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loockheed

water meth injection

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As a complete novice to this I would like to ask the panel which kit works the best for my link g4 , I will ask my mapper but would like to be fore armed with some good info so I can speak to him with some good understanding of the subject . the ecu is a g4plus on 2.2 cdb stroked to 2.35 Subaru.

thanks in advance

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I've also got a impreza ej20 v2. With the aem meth kit. I've yet to link it upto the g4+ yet, but pretty sure you can set it up so when it fails (I had a faulty wiring harness which caused intermittent cutouts) you can set it up as a input to give you a different boost/fuel table. There's probably a whole load of options and I'd be interested in seeing what any else has done. 

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I have water/meth setup controlled by the ecu ( g4+) ... the ecu drives the pump via a SSR and  I have it setup so that if the water/meth flow drops, tank gets below a set level or I just have it turned off, the ecu switches to a "safe" Fuel/Ignition and Boost table. When the tune is finished I can let you know how well it works or dosn't ;-)

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19 hours ago, lostsoul said:

I have water/meth setup controlled by the ecu ( g4+) ... the ecu drives the pump via a SSR and  I have it setup so that if the water/meth flow drops, tank gets below a set level or I just have it turned off, the ecu switches to a "safe" Fuel/Ignition and Boost table. When the tune is finished I can let you know how well it works or dosn't ;-)

Which kit do you have ? I can get hold of aqua mist or devils own with out a faf . I would imagine that there are preferences .

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Most kits are very similar...so really whatever takes your fancy.

If totally standalone, Aquamist is probably one of the better setups. But Prometh in the US is popular too, or Alky Control.

 

I'd avoid the push fit pneumatic fittings most use though. Yes they are very handy, but inevitably they will always leak over time and possibly fail. Or if you must use them, be prepared to change fittings every year for example as a maintenance measure.

 

Or it is easy enough to DIY build your own kit and control it from the ecu.

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Depends who's putting it all together and tuning it.

Using the ecu could save some money as it removes the need for an external controller, but there really are a few ways you could do it, each with various pros and cons.

 

Standalone setups are perhaps easier for a novice, but either way it will need tuned anyway so someone competent needs involved to get it all working properly.

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Devilsown will probably want you to use their controller, and kit in general obviously...and there's nothing wrong with that.

Really, discuss it with your tuner, to see what he can make work for you and your needs. If you can add a flow or pressure sensor on the line and apply any fuel/timing corrections based on that, then that can be the basis of a solid failsafe with regards tuning should the system fail.

Although done right, they are very reliable these days.

 

But with control on-board  the ecu and via a SSR for the pump or similar, it just gives the tuner a bit more flexibility with how "progressive" the delivery can be. If just PWM'ing the pump, as most aftermarket controllers do anyway, then it doesnt really need anything fancy, simple works.

So it's largely down to your tuner to decide how much water/meth they want to use, when they want to inject and how aggressive they might want any tuning to be

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I am using the devil's own tuner kit. They recommended letting my ecu controller it over their controller. 

I have the pump on a switch which also is connected to a digital input in my Link Extreme. When that digital input is active I use a 4d fuel/spark table to pull fuel, add timing and a duty cycle table with ssr to control a fast valve. This way the meth is always at 300 psi and the valve is pwm'd to pulse the spray. Works flawlessly. Dual 1000cc nozzles and a devil's own solenoid/fast valve. 

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On 11/27/2018 at 3:16 AM, 434josh said:

I am using the devil's own tuner kit. They recommended letting my ecu controller it over their controller. 

I have the pump on a switch which also is connected to a digital input in my Link Extreme. When that digital input is active I use a 4d fuel/spark table to pull fuel, add timing and a duty cycle table with ssr to control a fast valve. This way the meth is always at 300 psi and the valve is pwm'd to pulse the spray. Works flawlessly. Dual 1000cc nozzles and a devil's own solenoid/fast valve. 

You will never see 300psi, nor will 2x1000cc nozzles be as efficient as smaller nozzles. Well other than when the pump is pumping against the closed valve and if the pump has been adjusted to see a higher pressure.

 

In fact, with nozzles that large I'd be surprised if you ever see much over 100psi. The pumps simply do not flow what the suppliers claim, and any pressure claims are against a dead head.

I've tested the AEM big pump under load and in the real world at pressures required....realistically they're only around a 1200-1300cc pump, and that was with a quoted 1600cc worth of nozzle...and tested not fighting against boost pressure which would reduce flow further.

Even with only a 600cc nozzle...my  factory set 200psi pump, could never create 200psi.

 

With 1600cc worth of nozzle, in the car, in real world use max pressure I see is around 140psi....so if using say 40psi boost, that's now only 100psi of effective pressure to inject, so even less flow.

 

But stick a pressure sensor on the line and log it for yourself and use this to control any fuel/spark adjustments, rather than what you're currently doing which offers no failsafe. It's a cheap and easy way to monitor what the system is doing, and could be an eye opener.

It's a pity nobody seems to have done much testing on the various systems and pumps out there to prove or disprove the suppliers claims.

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