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Wow, Mafia,

Why did you install the nozzle so close to the inlet manifold?

(just different to other peoples installs)

Bill

I had a nozzle just before the intercooler and it made no difference. As long as it has enough distance to completely spread out on the intake pipe before it gets divided, thats cool. Either that, or you could do what some people are doing and fitting a nozzle to each inlet runner like the fuel injectors. Guarantees equal distribution.

You can either position it before the turbo is just before the throttle body. Nothing wrong with where it is :thumbsup:

You can get huge benifits going pre turbo, but its not very good for the compressor, water can deteriorate the wheel at a accelerated rate. BUT, I've seen compressors run about 10 times more efficient doing this, basically means pushing the efficiency range much higher. Kind of like moving the compressor map to the right

just wondering does the metho absorb more heat then water? for example for a air/water intercooler? how flammable is it?

thanks :whistling:

Methanol (not methylated spirits) can drop the inlet temperature by an extra 15 degrees. The water is not used as heat reducation at all, its actually there to slow the burn down and stop detonation. SLower burn means more torque, and more fuel stability

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You can get huge benifits going pre turbo, but its not very good for the compressor, water can deteriorate the wheel at a accelerated rate. BUT, I've seen compressors run about 10 times more efficient doing this, basically means pushing the efficiency range much higher. Kind of like moving the compressor map to the right

s3girl who runs a stock rb30et (apart from cams) with a gt42 on the same dyno as I pulled 470rwkw @26psi with water injection preturbo. He ran it like that for quite some time. Pulled the turbo off and no noticeable wear on the compressor. He did say pre turbo requires a shit load of water in comparison to the way you have fitted it up.

got a quick question, it as simple as installing then advancing the timing? (with precautions ie dyno and knock det) or do you actually need to get the car re tuned and advance it on the maps?

Edited by midnight

An long but interesting read here about water injection:

http://www.rbracing-rsr.com/waterinjection.html

Quoted from their site:

I Don’t Want To Learn...Just Give Me The Answers!

1. Maximum Torque occurs at a 13.2:1 Air Fuel Ratio.

2. Transitional Fueling and Maximum Boost Air Fuel Ratios are about 12.5:1.

3. Water Injection is most efficient with a 50/50 water alcohol (or methanol) mixture.

4. Methanol, as an additive, is not a practical choice as it is prone to pre-ignition in higher than 50/50 percentages, is not safe to handle, and is not readily available. It's a good choice, but not necessarily the most practical one when you need some in a hurry. Methanol is usually found where racing fuels are sold.

5. Denatured (ethanol) alcohol, typically 95% pure, is available in paint, hardware, and Home Depot type stores in gallon containers for about $10.00. Expensive but available everywhere. Isopropyl alcohol can be used but it is often 30% or more water by content.

6. Water Injection allows ignition timing to be more aggressive or closer to stock. In other words boost does not automatically mean retard your timing.

7. Excessive amounts of ignition retard will cause a loss of power and overheating.

8. Water to Fuel ratios should be based on weight and not volume.

9 . Water weighs 8.33 lb per gallon.

10. Alcohol weighs 6.63 lb per gallon.

11. Air weighs .080645 lb per cubic foot. It takes about 150 cubic feet of air per 100 horsepower. It takes about 12 lb of air per 100 horsepower.

12. Water or Water / Alcohol to Fuel Ratios are between 12.5% to 25%. This means Air to Fluid Ratios are between 11.1:1 and 10.0:1 with water injection.

13. Maximum water delivery should be in higher load low to mid rpm ranges tapering somewhat at peak rpms where load is less.

14. Atomization of the water mixture is directly related to it effectiveness. Finer droplets cool the inlet charge better and with less mass they navigate the inlet plenum easier for more equal water distribution.

15. Don’t flow water through an intercooler.

16. Atomized water, just like fuel , does not like to make turns thus making accurate distribution something to think about. This is why port fuel injection is the norm. Water is a fluid just like your fuel. Multiple nozzles, equally spaced in the plenum, although it complicates things, is a superior design.

17. The introduction of water will allow higher boost pressures to be run without detonation. Higher pressures will increase torque. It’s always about torque.

18. Racing high octane gasoline should be used for all forms of competition and for higher than normal boost levels. Water injection as well as charge cooling should be used with racing gas. 91/92 Octane pump gas simply will not cut it. Water spray cooling of the intercooler is a good idea.

19. Fuel Injectors operate in the 1 Millisecond range and are not capable of long term usage for H20 as they will corrode or rust shut in a very short period of time. Unless a solenoid can open as fast as a fuel injector it should not be used to "pulse" water injection events as flow is not directly related to "duty cycle".

20. Varying voltage to water injection pumps or using similar schemes is a recipe for disaster. You have to eliminate the variables, not increase them.

21. Fuel Injection pumps cannot be used for water injection. Water is conductive. Gasoline is not. Water will corrode an efi pump shut in a very short period of time.

22. Water injection has a cooling effect on the engine head, valves, and cylinder. Exhaust temperatures (EGT) are largely unaffected at recommended water / fuel ratios.

23. The cooling of potential hot spots in the combustion chamber defeats pre-ignition, the most destructive form of uncontrolled or unplanned combustion.

24. Higher static compression ratios will require a higher percentage of water or water / alcohol.

25. No, water does not burn. We are not combusting the hydrogen in the H2O.

26. At around 13.2:1 or fuel air ratios of .75, EGT’s will peak.

27. People will try to selectively edit their way to get you to use water injection by stating "One can basically double the power output of an engine using water/methanol" and "It was used effectively in Formula 1 before being banned for adding too much power". This is pure bunk. Water or water/alcohol/methanol does not make power...superchargers and turbochargers make power. The cooling effect of the water injection only allows you to run higher boost pressures and leaner mixtures without engine damage. The increased density or higher pressure ratio is what makes the power, not the water. The last time we checked water wasn't a very good fuel.

28. Ferrari suspended water in their fuel during their 1980’s Formula1 period. We don’t recommend that you try this...although Acetone will mix with water.

Edited by gtst25

Hi Mafia and all , this water/alcohol thing is getting too hard to ignore isn't it . Plainly all the benefits are there in charge cooling and the ability to run sane AFR's at high loads .

The thing I'd like to know is how sophisticated the control box is in injecting the water methanol mist . I can see instances where it would be an advantage to have it misting and not necessarily on boost .

What would work well is having the thing regulated off the AFM's signal so that its use would be air flow based rather than manifold pressure based .

Anyhow it seems to do the trick as is so I suppose the main gains would be fluid consumption , though its possible that we could run more light load (cruise) ignition advance and save some fuel as well . In the green stakes lower combustion temps possibly means lower NOx emissions with lean AFR's like 16:1 etc .

Will look into this one , cheers A .

Late edit They DO do a 0-5 volt MAF signal version of their stage 2 kit .

Edited by discopotato03

Late edit They DO do a 0-5 volt MAF signal version of their stage 2 kit .

Modern controllers offer 0-5V auxiliary input measurement or boost or any combinations, you're certainly not locked into using only boost.

Once you've connected the laptop and accessed the software, you can alter ramp rates to whatever you want.

Most users go for the simplest to install option.

The key to getting optimal results is in matching water:fuel:air ratios, and hence knowing the delivery ramp rate of fuel, and of the water system as well.

Maths will get a smart punter in the ballpark. :thumbsup:

Adrian's suggestion of using WI at low loads is not inherently bad, though we don' seem to have any evidence in the field that anyone does it. All the evidence points towards its benefits being an anti-detonant at high loads. For light load, it could be that virtually constant use would require a large storage tank - leading to packaging (size constraint) and excessive weight gain vs tangible benefit issues.

The other thing that might make a lot of work would be sizing nozzles capable of proper atomisation to match low fuel flow rates, and then having enough capacity to match the injectors when running at full noise. Sounds difficult unless using a high speed solenoid valve, which is expensive and might be difficult to interface with the ECU.

To me it is significant that the NACA aero research focused on WI as a way of running their engines at a higher maximum power output, while using lower grade fuel, and less of it. Replacing fuel with a certain amount of water improved military outcomes at a lower cost. The capacity of those aero engines, and power output meant that they were airborne fuel tankers with bombs and bullets. Literally able to consume hundreds of gallons of aviation fuel per hour. Military honchos had to work out how to stay in the fight but cut their fuel bills.

Particularly for a performance car application, I would stick with proven outcomes and target more reliable, knock free power at maybe slightly reduced fuel consumption.

Grigor's information is correct, and gearing your controller to take multiple inputs is relatively simple. Same as tuning your fuel and ignition, though the practice of getting it "right" may take some effort. All the same, Mafia's results are testimony to good outcomes using progressive delivery based solely on boost.

Edited by Dale FZ1

Yeah WI definitely food for thought . I can't decide if using say MAF or knock sensor input to suppress detonation is the go or just work along the lines of spray it in stay cool and avoid the detonation .

The site mentions diesel versions used to improve overall fuel consumption and in this day and age that's not insignificant .

Who knows , maybe a small nozzle for low load use and a larger one for extra volume when needed .

Mafia does your car just use the one in the cross over pipe ?

Cheers A .

Actually something just occurred to me , I wonder how this would go in an engine built with a higher static compression ratio that you'd normally use for a turbo engine - say 9.5 to 1 . This would in theory give more low down torque possibly allowing you to use the next size larger turbine housing and have a bit less restriction in the system - more top end potential too I suppose .

Thoughts ?

Edited by discopotato03

Not sure I understand this comment? Trigger the water flow according to the 0-5V MAF output, and pick up the pump duty cycle to suit. The highest % water:fuel is actually required around peak torque rpm because this is where peak work is actually done and detonation is most prevalent.

I can't decide if using say MAF or knock sensor input to suppress detonation is the go or just work along the lines of spray it in stay cool and avoid the detonation .

The performance diesel scene in the US is well versed in WI. Tractor pulls, and those lunatics who drag race their Dodge Ram utes and the like find great use for it. They do run boost pressures up around 90psi and have specific power outputs along the lines of a good petrol engine, so they are fueling them right up and would have combustion temps that would otherwise melt things. Obviously the water does a different job in a compression ignition engine.

As an aside, there is a Queensland company prototyping a secondary LPG injection system for use in light/medium trucks that seems to have great merit. The liquid gas acts to cool things and promote greater burn efficiency. They claim greater power/driveability and older engines are meeting current and future emissions targets. Packaging size would probably preclude its use in a Hyundai i30 or VW Polo though. :thumbsup:

Staged secondary nozzle activation could be done, but complexity is going upwards. If you were doing that, it would probably be wise to invest in a system that uses high speed solenoid water delivery. Basically works the same as a fuel injector but capable of handling water without corroding shut.

The site mentions diesel versions used to improve overall fuel consumption and in this day and age that's not insignificant .

Who knows , maybe a small nozzle for low load use and a larger one for extra volume when needed .

Higher compression has its merits, but the overall engine configuration has to be geared towards the overall power output. ie. you'd need to do a bit of homework on effective dynamic compression ratios which factors in cam profile + timing, and turbo spec. If you went too far out on a limb chasing efficiency then something relating to engine reliability is going to suffer. Depending on the approach to tuning with/for WI, it becomes an additional system that requires absolute reliability (NO failures) the same as fuel, cooling, and lubrication.

Fortunately there are some clever blokes out there, and some kits offer low water/nozzle blocked warnings and fail safe fuel/ignition mapping interventions. The point is that you would need to be careful as to how the WI is integrated into the tuning, and choice of engine spec.

I wonder how this would go in an engine built with a higher static compression ratio that you'd normally use for a turbo engine - say 9.5 to 1 . This would in theory give more low down torque possibly allowing you to use the next size larger turbine housing and have a bit less restriction in the system - more top end potential too I suppose .

Dale my thoughts in that first quote of mine was do we set the WI up purely to supress detonation or do we go like I think Mafia has and set it up for charge cooling and the performance benefits of lower charge temperatures as well as detonation prevention . I think option 2 would be simpler and more consistant . Option 1 would involve sophisticated means of detecting the onset of detonation and then triggering the WI system - sounds more complex than its worth .

My thoughts on diesels and fuel consumption came from looking at Snow Performances web site and some of their kits aimed at production NA diesel utes - American SUV's on steroids for the vertically challenged ...

The idear of the higher static CR is about making the engine develop more torque off boost , the possibility of the larger A/R turbine housing is about less turbine inlet pressure/reversion/pumping losses basically less heat so more advanced ignition timing if it makes a difference .

If memory serves me correctly someone mentioned once that Grp A RB26's used something like 9.4:1 CR though god only knows what rocket ship fuel they were burning .

I'm sure Mafia once said that it was possible to advance his engine to the point where power went backwards so beating the rattles in a high comp turbo engine should be doable - provided water distribution was even enough and you didn't want to run 40 pounds of boost .

For your average R33 punter something upwards of 260-270 engine Kw is as much as can be used (or got to the ground) so getting that output with 9.5:1 CR should be achievable .

WI or any similar means of supressing detonation always involves some risk , it would be up to the user to make sure it didn't run out .

Cheers A .

All of the available kits that I know of use some load-sensing method to trigger induction of water. That could be boost, or voltage from MAF or TPS. I don’t think that WI response to knock sensor output would be quick enough to control onset of detonation. So basically above the tuner’s preferred threshold the coolant (water, or water/meth) is used to prevent rather than eliminate knock that has already started.

There is a train of thought that nozzle placement further away from the inlet valve allows more time for conversion of the coolant from liquid to gaseous state, so there may be some air density increase depending on the installed location. Using a single nozzle could create the possibility of uneven distribution to cylinders, depending on manifold design and whether the conversion of state of the coolant facilitates less resistance to change of direction and distribution. Multi nozzle setups require some thought into even pressure distribution, so have their own design issues.

I agree the concept of higher static C.R. has its attractions, but it’s difficult to cite the Gibson Racing Group A cars as directly comparable examples. Reliable information from a mate who worked around the circus in those days indicates that the fuels were definitely exotic potions. No prizes for guessing why a certain red #17 car sponsored by Shell was acknowledged as about the most powerful of its breed.

I’ve looked at the 10:1 DE+T concept combined with water injection, but specific advice from a Cairns based expert was that the benefit:cost did not stack up well. There is much more off-boost torque to be had via cubic inches than via higher compression, for example.

The one thing that does seem to shine through is that there is a power level below which WI is of questionable value, and above which it’s extremely beneficial.

Good discussion BTW, and hopefully Mafia and others can chime in with some more experiences.

I was sniffing around NASIOC before because they have a section virtually dedicated to "Meth Injection" .

They have links to various suppliers in the US and some of the controller features look very interesting . One of them offers you a choice of two inputs ie a load voltage 0-5v signal from MAP/MAF and RPM and you set up a small table of something like 6x6 and the parameters are user definable . I'll have to get back with a brand (Coolamist ?) or a link if possible .

The idea of using pleb juice and WMI may help us a little at the pump each week .

There was talk of the poor yanks struggling with mouthwash 91-93 oct fuel at best and WMI getting them reliably over 100 effectively .

If ways can be found to properly regulate WMI even in off boost running cheap juice may be able to be used and still give reasonable power potential . Or you can look at it the other way and possibly be able to run best mean torque timing almost everywhere .

Anyhow between boost pressure/injector duty cycle/0-5v load sensor input lots of things are possible .

Cheers A .

I'll have to get back with a brand (Coolamist ?) or a link if possible .

There was talk of the poor yanks struggling with mouthwash 91-93 oct fuel at best and WMI getting them reliably over 100 effectively .

www.coolingmist.com

There is a different standard of rating octane in the US compared to Australia.

MON, RON, and RON+MON/2 all give different numbers for essentially the same level of knock resistance. If they are citing a number of 93, it's probably on par with our 98.

  • 4 years later...
  • 3 years later...

What an old read.

Just to correct one of my mistakes, I have learned over the years that the water what removes the heat, and the methanol increases the octane.

Together they drop the inlet charge temps quite a bit.

Not where I am............E85 only exists in the metro areas, its much easier to carry a 2 litre bottle of WMI for topping up the tank than it is carrying a 200 litre drum of E85.

But you are right, WMI doesn't quite produce the power gains that E85 does.

also WMI has that nothing nothing then HOLY FUUARKKK torque ramp because your timing jumps from nothing to a gazillion as you inject WMI..

Great for street/drift/drags etc.. not so great for track because it just fries tyres haha

also WMI has that nothing nothing then HOLY FUUARKKK torque ramp because your timing jumps from nothing to a gazillion as you inject WMI..

Great for street/drift/drags etc.. not so great for track because it just fries tyres haha

A good tune avoids this. I tuned mine to come on hard but not whack hard.

With my GT3076, I could drop it back to third at 100kmph (without popping the clutch / revs) and roll the throttle on and change lanes without the steering.

I would love my old setup back with a GTX, 25psi, and WMI.... would be a wicked streeter.

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