Water Injection Anybody??

[FordNut]

Water injection seems to be a popular mod for turbocharged or supercharged ricers (and some others such as Vipers and 'Vettes are listed or pictured on the suppliers' websites). The two most common names are Spearco and Aquamist. Anybody using it on their MM? From what I've read, it sounds like the most common fluid to use is actually a mixture of methanol/water instead of pure water. It is injected at a rate or about 10-25% of the flow rate of fuel. I suppose this amount of methanol would not violate any sanctioning body rules regarding fuel type, since pump gas commonly contains some alcohol? Anybody have any experience with these systems?

[Fourth Horseman]

What does water injection do, anyway? I mean, what benefit does it yield? I've been wondering about this for a while, but haven't talked to anybody who knows much about it.

[RCSignals]

water injection has been around for a while. it used to be touted as a fuel consumption lowering device for Motrohomes etc.

[looking97233]

Water injection lowers the intake temprture. hence it is used alot on turbocharged cars.

[DirtyDog]

In the sixties we used to hook up a window washer squirted to spray a mist into the carburetor. It would give a cooling affect and slow the burn. It would give you a little power and legal. But there was not much of a metering system like today to get the mix right and dependable.


Dave

[MARAUDER S/C #5]

In the sixties we used to hook up a window washer squirted to spray a mist into the carburetor. It would give a cooling affect and slow the burn. It would give you a little power and legal. But there was not much of a metering system like today to get the mix right and dependable.


Dave
Nice to have a dirty dog in the house! :up:

[MARAUDER S/C #5]

Nice to have a dirty dog in the house! :up:
Sorry, Dirty Dog...............

[David Morton]

Water/Methanol injection not only cools the intake charge it also raises the effective octane value of the charge so that the PCM can run more timing. Methanol has an octane of 160! It's also pretty expensive. These systems are safe as long as you don't go messing with the fueling tune or try to get away with more boost pressure. If you're hard into it and the tank runs dry you might burn a hole in a piston or two.

The water will keep those pistons and valves cleaned of any carbon build-up, but you can always just pour some water in the engine (slowly) and clean that stuff off when you get a little pingy from increased compression ratio when it builds up.

To me the systems are an extra fuel requirement and make me have to check the tank every day and it's just not worth it to me. I won't be getting one.

[BillyGman]

I remember water injection units being sold in local speed shops back in the 80's for carbureted engines. It was advertised to be a preventative of knocking and pinging which allegedly allowed you to use lower octane pump gas on high compression engines w/out having to retard the ignition timing.


I was always skeptical of the very thought of watering down the air/fuel mixture though. It just doesn't sound right to me. However, I can't say that I ever tried it. It just always sounded like a gimmick to me. I never heard of it having a cooling effect on the intake charge. I'm even more skeptical about that claim. Again, this is simply an educated guess, but that sounds like a mere sales pitch to me. Using a cool can w/ice in it would certainly have a greater cooling effect than water that's used at room temperature at best. Alcohol/Methanol has a cooler temperature than water, however since it's being diluted w/water, it will not have any real cooling effect to my knowledge. Even if it were used undiluted, I doubt that it's cold enough anyway to have any noticeable cooling effect.

[MikesMerc]

Water injection works. Its been proven.

Practicality is the issue though. Variables such as metering, humidity, ambient temp, and fuel quality make tuning a real chore. A tune that might make more power one day under one set of conditions, may end up costing power on another day. The area of proper tune is very narrow for a street car.

Lowering the intake charge is = to raising the octane level BTW.

When it comes to street cars, skip the water injection and looking into improved inter cooling.

[FordNut]

The concept should work, based on theory. The fine mist of water (whether mixed with alcohol or not) evaporates easily. It must be a fine mist, not a spray. When the water evaporates, the phase change from liquid to vapor removes heat from the air stream. It would probably not work very well on a roots type blower system, but should work well on a turbo or a centrifugal blower equipped car. The cooler air charge allows you to run more timing, or in our case it would prevent pinging, thereby preventing the knock sensors from pulling timing (bottom line, same effect).

The consumption rate based on the units available at the posted manufacturers' websites, is about a tank of water to a tank of gas. Many of the systems simply use the windshield washer reservoir for a tank, so just top it off with water when you fillup with gas if you don't have any alcohol at the time. Actually, if it runs out, the car would just revert to running as if you don't have the system so there should not be a problem, except to protect the pump on the injection system itself (not good to run pumps dry for long).

According to the websites of the manufacturers, the octane rating of methanol is actually closer to 120 or so. But it is only mixed about 50/50 with water (pure methanol actually increases the air temperature instead of reducing it), and it is only injected at 10-25% water/fuel ratio. That is about 0.5-2.5% methanol/fuel ratio, so the octane increase is minute. The temperature drop is the biggest benefit, it is like installing a more efficient intercooler.

A side benefit would be the cleaning effect on the inside of the engine.

Who is gonna go first?

edit: I reckon it should be installed after the intercooler and before the IAT sensor for maximum benefit.

[dwasson]

Water injection was first used in aircraft engines before WWII when it was discovered that altitude caused bad pinging. In the early 60's Oldsmobile sold a turbo charged F-85 that included a water injection system. From what I've read/seen normally aspirated engines may not get a lot of benefit from water injection but it is most useful in a turbo or supercharged application. I think that water injection can cool the intake carge more than an intercooler will. Granted, the hassle of checking one more fluid may make water injection less user friendly but the benefits of the system have been proven in many applications for decades.

It works.

[MikesMerc]

Oh, it definitely works. It's the tuning that's the real issue. Plug and play these systems are not.

Depending on the variables mentioned above, intake charge cooling will vary quite bit. The cooling provided by water injection systems takes place after the inlet temp sensor so the PCM has no method to compensate for such variations. Intercoolers can be much more consistent in thier inlet charge temp reduction and don't need the PCM to adjust anything.

I'm not too sure about any claims that say that "the motor goes back to running normally when the tank runs dry". Unless there is a sensor telling the PCM that the tank is empty and to pull timing out, bad things can happen. And if the motor is tuned with enough safety to run with a dry tank, what's the point. That's like tuning an intercooled blown motor to run okay without the intercooler....pretty silly.

Tuning is the real issue with these systems. The manufacturer's websites do a fine job at glossing over all the fine details :)

[BillyGman]

This has been a very thought provoking thread so far, however I still think that having a cool can will have more of a cooling effect than water injection would. I've never seen any racers w/water injection on their cars, but perhaps that's merely because I haven't been going to the track for years. Have any of you guys ever seen cars at the track that had water injection? If there's any performance benefit to be had, then I would think that somebody at the track would have this.Perhaps it's because the tuning issues that Mike's been talking about.

[MikesMerc]

I've seen water injection a couple of times at the track over the years. They have always been on all out track cars though. In addition, these were carbureted cars that had no PCM. That kind of tuning technology is akin to using a large steak knife for brain surgery over a precision scalpel. Modern cars require for more precision tuning.

Not saying it cannot be done...just that water injection for the street is impractical (until they resolve day to day tuning issues).

[DirtyDog]

The cooling effect is not at the air intake that is measurable, it’s inside the cylinder when the fuel burns. The fuel burns slower and therefore not as hot. It burns more like it has 96 octane instead of 92 octane. (Hypothetical numbers)

I think 92 to 92.5 octane would have been a set of numers to use.

I think Nitrous is a bigger bang for the buck and more controlable.

Dave

[MikesMerc]

The cooling effect is not at the air intake that is measurable, it’s inside the cylinder when the fuel burns.

Which is precisely why it is so difficult to tune for. Given all the variables that effect the level of cooling provided by a water injection system (such as the tank running dry :eek: ) there is no ability for the PCM to compensate. That's why tuning for water injection is very similar to tuning for nitrous, and why you don't see nitrous cars as daily drivers (with the nitrous always engaged).

[FordNut]

Just thinking it may be a way for some members to pick up some power. Seems like everybody has made comments without even looking at the Aquamist website, which has a lot of useful information.

They have a sophisticated control system for the top-of-the-line models which can in fact trigger a PCM to pull timing or a turbo system to pull boost (I guess by using the waste gate?) but I'm not sure if you could adjust boost on a supercharged system. Also it uses a pressure switch to only open the injector valve when boost reaches a preset, adjustable level.

The cooling effect is actually BOTH physical cooling of the intake air and slower burning in the cylinders.

F1 and Rallye cars commonly use it in competition, but there is increasing interest for street use both for performance gains and improved fuel economy.

One of the websites stated that isopropyl alcohol could be used instead of methanol. That's rubbing alcohol, available at 91% for less than a buck a bottle at the corner drug store.

[MikesMerc]

Just thinking it may be a way for some members to pick up some power. Seems like everybody has made comments without even looking at the Aquamist website, which has a lot of useful information.

I'm not poo-pooing the idea, just being honest about what I already know about water injection.

As for the information on the website, I have read it. I also made my comments above in the thread about what I think about manufacturer's claims.


The cooling effect is actually BOTH physical cooling of the intake air and slower burning in the cylinders.


Cooling the intake charge slows the burn. It's the same thing. This "cool" intake charge is not to be confused with significantly cooler ambient temps which result in more air molecules being packed into the cylinder on the intake stroke.



They have a sophisticated control system for the top-of-the-line models which can in fact trigger a PCM to pull timing or a turbo system to pull boost (I guess by using the waste gate?) but I'm not sure if you could adjust boost on a supercharged system. Also it uses a pressure switch to only open the injector valve when boost reaches a preset, adjustable level.

Sounds a lot like a nitrous tune. Hmmmmm....who already said that;)


Don't get me wrong, its a nice idea. When the technology becomes practical and predictable for day to day use, I'll be there. Until then, I'll watch this one from the side lines. I've already did the nitrous thing and have had my fill of playing with additives to the intake charge:) I'd like to see some else give it go though.

[FordNut]

More info found at SVTPERFORMANCE.COM

Snow performance makes kits specifically for Mustangs, lots of people are using pure alcohol instead of water or a mixture in spite of what was posted previously.

An extracted post follows:

There is little benefit to a race truck. You are correct on that. There is a HUGE benefit on a street truck wanting to run race amounts of timing on pump gas. No way to argue the point. Won't leave quite as hard as the race setup due to the extra timing you can't add down low under non-boost areas. Can't have that extra timing with the alcohol injection since you don't inject it except under boost. My chassis dyno was within 1.5 rwhp and 5 rwtq of my race setting with the alcohol and 91 octane. I used to lose 30 rwhp and 40 rwtq between race and 91 octane programs. That's who these kits are for, guys like me who want the max on pump gas. In my case the alcohol kit is worth 28.5 rwhp and 35 rwtq. That's real good bang-for-the-buck in my opinion.

[MikesMerc]

Many other safer ways to find that kind of power...not to mention a source of power that doesn't need to be refilled.

By the time you've made other more effective and permanent power mods than the water injection, you've already lost practical streetability anyway.

Like I said, same problems as with nitrous. A completely different combustion effect, but the same issues none the less.

[FordNut]

Not at all like nitrous. I can get water and alcohol at any Wal-Mart, grocery store, or drug store. Not so with nitrous. And sometimes rules dictate only one power adder. Nitrous on top of a s/c would not be permitted, but water injection would.

And when all the other "permanent" mods are done and you still want more power, this seems like an easy way to get it.

Like the exhaust, underdrive pulleys, electric water pump, when they were first suggested in these forums all the replies were from naysayers, but when somebody finally tried it all that changed. Since I'm not blown, I can't try this one (at least not to its full potential) but somebody will.

[dwasson]

It seems to me that the knock sensors on modern PCM cars are not used as much as they used to be. We used to be able to scope a car and tap the block with a hammer and watch the timing retard on the scope. It seems to me that there is no reason for a modern car to ever ping, no matter what you do to it. If the knock sensor sees incipiant detonation it should retard the spark until that isn't a problem. In that case then running out of water in the injection tank wouldn't cause pinging.

Now, I know that the Marauder will ping on bad gas and I'm forced to ask why. Why doesn't the PCM retard the timing enough that if I ran regular I would just lose performance?

Any of you mechanic types know why?

[FordNut]

It seems to me that the knock sensors on modern PCM cars are not used as much as they used to be. We used to be able to scope a car and tap the block with a hammer and watch the timing retard on the scope. It seems to me that there is no reason for a modern car to ever ping, no matter what you do to it. If the knock sensor sees incipiant detonation it should retard the spark until that isn't a problem. In that case then running out of water in the injection tank wouldn't cause pinging.

Now, I know that the Marauder will ping on bad gas and I'm forced to ask why. Why doesn't the PCM retard the timing enough that if I ran regular I would just lose performance?

Any of you mechanic types know why?
I can't answer your question but I can expound on one item. When running a supercharger with lots of boost on an already high compression engine the response of knock sensors is claimed to be too slow (I'm not a tuner, just repeating what I've heard) in that if it ever knocks it's too late.

I've been reading about folks using the water/alcohol injection system and running over 20 lb (one GNX owner claims to run 29 lb) boost.

[dwasson]

I can't answer your question but I can expound on one item. When running a supercharger with lots of boost on an already high compression engine the response of knock sensors is claimed to be too slow (I'm not a tuner, just repeating what I've heard) in that if it ever knocks it's too late.

That makes sense. That also may be why Ford added a second knock sensor the the 2004 motor.

It may not be true but it sounds plausible. Thanks.

[MikesMerc]

Not at all like nitrous. I can get water and alcohol at any Wal-Mart, grocery store, or drug store. .

Yes it is....you just totally missed my point.

I'm not talking about power adders, I'm referring to all the issues you have with TUNING a STREET driven nitrous car. I'll repeat some issues for those that missed it....you have ambient temp and humidity issues, you have a bottle that "runs dry" requiring re fill (no matter where you get the stuff) making tuning "around" the possibility of a dry tank, and you have to concern yourself with a clean and even atomization of the injected water/alcohol through out all cylinders. It would be a real bummer if some cylinders received less than others as those would detonate sooner.

These are real tuning issues. Face it...water injection has been around for 60 + years and it has not yet been accepted as mainstream high performance technology. There is a reason behind that....and it isn't from not having enough adventurous folks to try it:)


And when all the other "permanent" mods are done and you still want more power, this seems like an easy way to get it.

Really? For a STREET car? If you've gone far enough to hard mod everything you can to a car to eek out every 35 hp gain, it would hardly be called a street car anymore. In addition, if its just that important to squeeze the last iota of power out, do what most serious folks do and just run turbo blue (or another race gas of choice) and just call it a day. It will end up running much more predictibly, be easier to tune, and you won't need to refill the bottle.


Like the exhaust, underdrive pulleys, electric water pump, when they were first suggested in these forums all the replies were from naysayers, but when somebody finally tried it all that changed.

Ummmm...not sure who the "naysayers" were, but those items you rattled off are quite mainstream compared to water injection. I had all three of those mods on my 5.0 mustang back in 1988 not a month after I had it:D Far from cutting edge stuff I'm afraid:)



It seems to me that the knock sensors on modern PCM cars are not used as much as they used to be. We used to be able to scope a car and tap the block with a hammer and watch the timing retard on the scope. It seems to me that there is no reason for a modern car to ever ping, no matter what you do to it. If the knock sensor sees incipiant detonation it should retard the spark until that isn't a problem. In that case then running out of water in the injection tank wouldn't cause pinging.

Now, I know that the Marauder will ping on bad gas and I'm forced to ask why. Why doesn't the PCM retard the timing enough that if I ran regular I would just lose performance?

Any of you mechanic types know why?


Dan,

The variation in burn when running water/alcohol injection is just far too wide for the PCM to handle. The knock sensors are there for the occassional bad tank of gas...not as a performance tuning mechanism.

Two reasons for the pinging....one, Ford knock sensors suck. Sorry but its true. Two, the motor is already running 10:1 and prone to detonation issues. A knock sensor is just not going to be able to swing enough to avoid the issues on an aggressively tuned 10:1 motor.

Fordnut is right about one thing....under hard boost, once the knock sensor reacts, its too late.


Again, I'm not naysaying for the heck of it. The technology has been around a long time and has not taken off. Think about it...if the idea was good, there sure as heck would be ALOT more folks running it. The reality is that the technology is met with very mixed reviews from those qualified to form an opinion. That tells you something about the predictability of the results. A small handful of folks running it does not make it a good mod.

[David Morton]

It seems to me that the knock sensors on modern PCM cars are not used as much as they used to be. We used to be able to scope a car and tap the block with a hammer and watch the timing retard on the scope. It seems to me that there is no reason for a modern car to ever ping, no matter what you do to it. If the knock sensor sees incipiant detonation it should retard the spark until that isn't a problem. In that case then running out of water in the injection tank wouldn't cause pinging.

Now, I know that the Marauder will ping on bad gas and I'm forced to ask why. Why doesn't the PCM retard the timing enough that if I ran regular I would just lose performance?

Any of you mechanic types know why?Did somebody actually want to hear from an ASE Certified Master Technician? Well I'm one and here's the skinny on "detonation" and how the knock sensor works. Attention, class is now in session. First, let's stop saying "detonation" when we mean knock.

Things happen pretty fast inside a cylider and the spark must be started way before the piston actually completes it's compression cycle. If not, the lions share of the power of the explosion will just go out the exhaust pipes making a loud noise. Knock, aka. "detonation" is when the hammer blow of exploding gas (aka. lions share) inside a cylinder whacks the piston far enough before it reaches TDC to compress the oil in any and or all of the following causing metal to metal contact: rod bearing/journal, wrist pin/piston and piston/cylinder wall. This is also trying to push the crankshaft in the wrong direction so it robs power. I haven't heard a tune-up guy yet in the 20 some odd years since the knock sensor has been in use say anything other than "they suck", except the few that really understand what's going on and that there will never be a computer fast enough to interrupt that process. Once the flame has started there isn't any way to stop it.

Sometimes knock occurs because spark timing is too far advanced. With 91 octane, a given amount of advance won't knock where it will with 89 octane. Engine load, vacuum, and air density (Barometric pressure + moisture) also affect the speed of flame propagation and factor into the timing curve. Computer controlled ignition has always tried to get the most timing by trial and error and uses the knock sensor to do this. It's why it's there. Most engines today walk the tightwire of timing and are experiencing levels of "knock" that most of us don't hear. The computers sense a slight knock and back off timing for the next firing cycle, they're a hundred times over fast enough to do this. They're also smart enough now to know the difference between engine knock and hammer blows or anything else, like say main bearing knock. As long as there is computer controlled ignition on internal combustion engines, there will be a knock sensor. It's another reason we get good mileage with these powerful engines.

But other times knock occurs before the spark plug ignites. This is now called pre-ignition, formerly called pre-"detonation". This is caused by the same factors as before but when pre-ignition is present the knock sensor and computer are still trying to back off the spark, which isn't the cause of the knock, and so continue to retard timing until enough power is robbed from the cylinders that aren't knocking that the pre-ignition gets reigned in by attrition. When inadequate octane is the cause, timing usually gets dropped of to maximum and the knock continues, eventually resulting in engine damage. Maximum retard is designed to be before that "lions share" is going out the exhaust because that would superheat the catalytic convertor and shoot the emissions off the chart. But in the case of true pre-detonation, it just dogs the engine until you stop trying or something breaks.

Read chapters 2 & 3 and have your answers to the questions on those by the end of the day tomorrow.

Class dismissed. :lol:

[FordNut]

Yes it is....you just totally missed my point.
You missed my point. But your mind is made up. Somebody else will try it. Maybe after checking the posts at SVTPERVORMANCE or MODULARFORDS.


tuning "around" the possibility of a dry tank
No, that's not necessarily true.


Face it...water injection has been around for 60 + years and it has not yet been accepted as mainstream high performance technology. There is a reason behind that....and it isn't from not having enough adventurous folks to try it:)
Right, the reason is that people haven't quite got it figured out yet, but we're smarter than we were 60 years ago.


Really? For a STREET car? If you've gone far enough to hard mod everything you can to a car to eek out every 35 hp gain, it would hardly be called a street car anymore. In addition, if its just that important to squeeze the last iota of power out, do what most serious folks do and just run turbo blue (or another race gas of choice) and just call it a day. It will end up running much more predictibly, be easier to tune, and you won't need to refill the bottle.
Actually I know of a few cars that have been pushed to the limits and are still street driven, some more than others. Turbo Blue isn't that easy to find. Race gas contains lead and will kill catalytic converters. Both cost lots more than water/methanol.


not sure who the "naysayers" were, but those items you rattled off are quite mainstream compared to water injection. I had all three of those mods on my 5.0 mustang back in 1988 not a month after I had it
I guess you weren't around here in those days. Those items were commonly accepted for Mustangs even at the time they were poo-pooed here. Just like water injection, which is becoming more common on Mustangs now.

If it weren't for a few people innovating and experimenting, you wouldn't have a blower sitting on your car now.

[MikesMerc]

You missed my point.

Ummm....what point did you make? I originally said that the tuning issues for water injection were similar to tuning with nitrous. You replied with a comment about the ease of filling the bottle which has nothing to do with TUNING. I have no idea what connection you're trying to make here. :confused:


No, that's not necessarily true

No....it isn't. But, we don't live in a world of absolutes. I'd sure hate to be poor sole who was at WOT when the tank goes dry without any contingency mechanism...lol. Tuning around a "dry tank" not necessarily true? Perhaps. Foolish not too? Absolutely.



Right, the reason is that people haven't quite got it figured out yet, but we're smarter than we were 60 years ago.


Sure, but how about smarter than we were last year or the year before? The innovation of the technology has been one iota above dormant for the last decade. I wonder why? :rolleyes:


Actually I know of a few cars that have been pushed to the limits and are still street driven, some more than others.

Everyone's opinion of what is "streetable" varies. That said, you'd be hard pressed to prove that most members of this BBS would feel that a car pushed to the edge is "streetable".


Race gas contains lead and will kill catalytic converters.


Not all race gas is leaded. Check your facts.




I guess you weren't around here in those days. Those items were commonly accepted for Mustangs even at the time they were poo-pooed here. Just like water injection, which is becoming more common on Mustangs now.


Poor analogy I'm afraid.

Gears and under drive pullies have been proven technologies for decades. Water injection is still completely unproven. It is not generally accepted by enthusiasts as a consistent and reliable modification. That's precisely why we don't see it around much. A few mustang guys looking for the next gimmick does not prove a technology is ready for prime time, or that it will ever be.



If it weren't for a few people innovating and experimenting, you wouldn't have a blower sitting on your car now.

True. I have nothing against innovation. Unfortunately there is nothing innovative about water injection. Its an old technology that has gone nowhere for the most part.

The trouble is that there are just easier and more reliable ways to make the same power. True enthusiasts know this and is exactly why the technology has lamented. A few guys over on the SVT or other forums that have tried it does not make it a bona fide technology I'm ready to recommend to anyone. I've seen it in action with my own eyes and it was not impressive. Unless there are some siginifcant advances in the technology, its going to stay on the same level as header wrap (a nice idea that doesn't work).

[David Morton]

Looks like we need a class on 'tuning'. Maybe we can get a little clarity here before this argument goes ballistic. All students please refer to my class on "detonation" as it will contain much information pertinent to the discussion. Class is now in session. :bounce:

The Powertrain Control Module is programmed with parameters that control ignition timing and fuel metering. Someday it will even control valve timing when they find a reliable way to electrically open and close the valves, but that looks like a ways off. For now, let's just concentrate on what the PCM can control.

Ignition timing, as we learned in the previous lesson, is being controlled by the PCM largely by the use of the knock sensor and for the most part is useless when pre-ignition is causing knock. There isn't much we can do to mitigate the effects of low octane fuel on a high compression engine using ignition timing, so "tuning" in this area is not effective.

We can, however, have a huge effect on knock in the area of fuel metering. We can add water injection, essentially a fueling additive, and run with less octane and not cause pre-ignition. Or, we can "tune" the fuel metering curve, changing the parameters programmed in the PCM, to richen the mixture when the conditions for pre-ignition are ripe and prevent detonation that way. The fuel metering parameters are best represented as a 'plane' or 'landscape' because several things figure into the calculations of fuel requirement. Some of these are; RPM's, air density, exhaust oxygen content, and load requirement using inputs from tachometer, Mass Air Flow sensor , Exhaust oxygen sensor and Throttle Position Sensor . Some PCM also use Manifold Absolute Pressure as a modifier for TPS. To date, I know of no PCM that adjusts this program using input from the knock sensor. It does not care if the engine is knocking. This is largely because the EPA doesn't care either. They only care that the program does it's best to maintain a 14.7 to 1 air to fuel ratio which will give the best emissions.

When tuners change the programming of the PCM to compensate for a supercharger or turbocharger, it is mostly the fuel metering that they are "tuning". They are very experienced men that know what will hold an engine together when a supercharger or turbocharger is packing extra air into those cylinders.

The guys that are experiencing extra HP from water injection are enjoying more timing advance because the knock sensor controlled PCM ignition curve is making the most of the denser charge and when they run out of water, they will still be OK, their PCM will adjust. It is where the idea that we can "tune" the fuel metering with a mind towards running water injection (and we can) is where we flirt with disaster, for if we do this, and the tank runs dry, we may burn holes in the pistons.

Come to think of it, I'll just use Trilogy's proven tune program when I get the venerable supercharger, (it doesn't make allowances for water injection) and get the darn water mist system anyways and take advantage of the extra timing. Why not?

[Joe Walsh]

Hey Guys, Check out article in July 04 Muscle Mustangs & Fast Fords...
They tested Snow Performance's Methanol Injestion Kit. The Kit looks
pretty well engineered and includes an adjustable control module plus a
realpump, not a windshield washer pump. They put it on a Vortech
blown Mustang and recalibrated fuel curve + more timing and got 80HP.
(www.snowperformance.net) If you were running some serious boost on
your MM it probably would help..but you would have to burn a new chip
to take advantage of the Methanol's cooling effect.

[David Morton]

If it messes with the fuel, I don't want it.

[BillyGman]

If it messes with the fuel, I don't want it.
That's kinda how I feel about it too. I still don't think watering down the gasoline is the way to go. Just my 2 cents. To each their own, but any of you think it's so great, then please be our guest and try it out on YOUR Marauders and then you can let the rest of us know how you did, and if you would really keep the water injection on there as a permanent modification. I highly doubt it.

[MikesMerc]

The guys that are experiencing extra HP from water injection are enjoying more timing advance because the knock sensor controlled PCM ignition curve is making the most of the denser charge and when they run out of water, they will still be OK, their PCM will adjust. It is where the idea that we can "tune" the fuel metering with a mind towards running water injection (and we can) is where we flirt with disaster, for if we do this, and the tank runs dry, we may burn holes in the pistons.


Exactly.

And the trouble is that I've yet to read an article where any significant HP gains have NOT been from leaning out the fuel curve (in addition to kicking up the timing) to take advantage of the water injection.

This is precisely what I meant when I referred to the problems of "tuning around a dry bottle". I've been down this debate road before and I didn't just fall off the turnip truck :cool:

[Ross]

So, for the sake of argument, assuming that this is a mod which could be of benefit under the right circumstances, is it something which is only of value to SC or TC engines? Is it (theoretically) of any value to NA engines? Not that I'm planning to run out and buy one, just wondering how closely I should keep monitoring this thread.

[RF Overlord]

Is it (theoretically) of any value to NA engines? ... just wondering how closely I should keep monitoring this thread.

Excellent point, Ross...

[merc406]

I didn't read everything here, but I did use w/i back in 77 on my 429SCJ, not for more power but just to keep the thing from knocking on the gas that was going down in quality fast back then. I did keep the same power level but it didn't make more with it. It made driving on the street possible.
I also kept it with the nitrous I built for it.

[FordNut]

So, for the sake of argument, assuming that this is a mod which could be of benefit under the right circumstances, is it something which is only of value to SC or TC engines? Is it (theoretically) of any value to NA engines? Not that I'm planning to run out and buy one, just wondering how closely I should keep monitoring this thread.
Based on what I've learned so far, it has minimal benefit for a NA engine. Maybe 5 hp. But it does open up the possibility of using lower octane fuel and maintaining the same power levels, saving a little $$$ on gas.

[David Morton]

...But it does open up the possibility of using lower octane fuel and maintaining the same power levels, saving a little $$$ on gas.A possibility, just don't let the tank run dry while you're trying to spank some Camaro or he might wind up putting you over his knee.

Oh, and MikesMerc. You have always seemed to me to be well educated in automobile technology and I never had the idea you had fallen off a turnip truck.

Maybe a kielbasa truck, but never a turnip truck. :lol: :beer:

[MikesMerc]

Maybe a kielbasa truck, but never a turnip truck. :lol: :beer:

:lol: :lol: :lol: