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CoupleOvans
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I am wondering if water injection would make any power on a NA motor?

Reason I ask is my acclaim seems to pull harder on rainy days, when my intake would be pulling water from my hood scoop.
 

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you need a lot of heat, so you'd have to be running pretty lean. Normally the heat of boost will shock the nitrogen out of the water, NA would be tough
 

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there is no nitrogen in water. and if there were that would only lower your hp. its the oxygen that you are looking for, you do need heat to get the O2 to seperate from the H but this has been done in supercharged and n/a aircraft engines since ww1. if done right it will work just not as well as in a turbo engine.
 

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I have heard of guys doing alcohol injection on N/A motors!!!!
 

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there is no nitrogen in water. and if there were that would only lower your hp. its the oxygen that you are looking for, you do need heat to get the O2 to seperate from the H but this has been done in supercharged and n/a aircraft engines since ww1. if done right it will work just not as well as in a turbo engine.
The devils own system cost about the same as a nitrous system, also since the early days of war LMAO. If your going to spend the money and go through the trouble of driving a car "on the bottle" at least put something in there worth the trouble. Nitrous will make you faster, even a little bit, dry or wet system. Even with a turbo the gains are small with water, unless it fills a MASSIVE tuning hole.
 

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I have heard of guys doing alcohol injection on N/A motors!!!!
In my experience a NA engine can take water and gain efficiency/power.
Much less so with alky mixes.
The issue I always got looped back to is control of the water.
You will only gain power or fuel efficiency if you can increase the spark advance and reduce fuel while it is spraying.
I always wanted the water to be a redundant measure and wasn't willing to alter the spark and fuel curves in case the tank emptied or the injector(s) stuck. But without adding advance and pulling fuel your really just bogging the engine. Even if your reducing intake temps the water occupies space in the cylinder requiring fuel removal to compensate or you run at least slightly richer (in some cases quit a bit more rich) and the water also slows the flame front during ignition requiring more advance otherwise the fuel mix doesn't burn in the desired time frame.

If your willing to a custom cal that compensates then you can use the tps sensor output to trigger the system, prime the pump at one throttle level and open the solenoid at another allowing you to run water under load in a NA application.

If your like me and hoping to see some gains from running water but not willing to risk remapping the calibration then there is no point in a pressurized system. You WILL lose power and efficiency.

Perhaps for older carb set-ups you could shave the head and advance the dizzy a little and then run vac fed system with no pump where the water is pulled from its resevoir by venturi effect. I still would not mount a pump system.
 

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CoupleOvans
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Discussion Starter #10
Good info. I was only askin cause both my cars seem to pull harder on rainy days.
 

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I've kicked around the idea of water injection for many years without ever acting on it. i was just getting ready to start on my turbo GTS...when I sold it. Now I have a 3.0 and though the benefits of water injection are less, I think there are still possibilities. To be clear, I wasn't looking for power gains. I wanted to stop buying premium gas. I was looking to increase the octane rating of my regular gas with water injection. At 30 cents a gallon less, the system would pay for itself. With the 3.0 I can still raise my compression and advance the timing while using water, but as mentioned above, I better keep my water supply full.
 

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I understand, and I promise I'm not trying to be a wet blanket.
But you have to think about how the car is going to use that lower octane fuel when it doesn't understand that your spraying water into the intake track. I've been down this road, thinking I could just clock the dizzy to achieve some compensation but the ignition curve is not linear. In order for the car to make use of the water at all you need to be able add ignition advance and/or cut fuel. Without the ability to do so you will not get a mpg benefit, power benefit, or gain the ability to run lower octane fuel. If you read around the common manufacturers websites they will disclose in detail that you MUST have the ability to alter fuel and timing to make use of their product. Sorry if thats bad news, been there myself.

Cheers...
 

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I understand and appreciate your input.
Unfortunately, sometimes I can't control my own curiosity. It would certainly make more sense for a turbo car, but unless I turbo that 3.0 somewhere way down the road, I'll just have to experiment with what I have. That is part of the reason I have these old cars.
Even a bad result is an answer.
 

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I understand and appreciate your input.
Unfortunately, sometimes I can't control my own curiosity. It would certainly make more sense for a turbo car, but unless I turbo that 3.0 somewhere way down the road, I'll just have to experiment with what I have. That is part of the reason I have these old cars.
Even a bad result is an answer.
In that case you may want to consider a vacuum drawn system. It is cheaper, and simpler because there is no need for a pump. NA engines produce higher vacuum under load, even during acceleration once the butterfly is open. This would induce injection only under vacuum greater than the cracking pressure of a check-valve. It will use the fluid slowly, and there would be no need for any methanol/ethanol/etc. This will cause a predictable drop in charge volume and increase the fuel mixture based on the nozzle and check valve you select. Atomization won't be as fine so you'll have to place the injection site(s) accordingly. Be careful to monitor fluid usage, you don't want to wash down the cylinders or contaminate your oil, though this is less likely without a pump. Good luck, and report back.
 

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Thanks for the help. As I just got the car, I'll be running several tanks of gas through to get a good baseline on performance and MPG. After I get a good feel of where the car is at then I'll start making the changes one by one. I'll report back, good or bad.
 

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I've kicked around the idea of water injection for many years without ever acting on it. i was just getting ready to start on my turbo GTS...when I sold it. Now I have a 3.0 and though the benefits of water injection are less, I think there are still possibilities. To be clear, I wasn't looking for power gains. I wanted to stop buying premium gas. I was looking to increase the octane rating of my regular gas with water injection. At 30 cents a gallon less, the system would pay for itself. With the 3.0 I can still raise my compression and advance the timing while using water, but as mentioned above, I better keep my water supply full.
That is what i have looked into water/alky injection for, is an effective octane increase or more specifically to eliminate detonation without having to buy expensive high octane fuels.

Yes just to add it to a stock motor without having a need for it, it does nothing for power, just like 100 octane fuel when all you need is 87 Octane is not going to get you more power.

But 100 octane will allow you to crank up your timing or compression thus ending up with more power .

Same with the WI it in and of itself does not add power, it may cool the intake charge a bit, but that can be canceled out by things mentioned above.
But, the WI allows you to turn up your timing, boost, etc that can result in more power, and usually cheaper than $8+ a gallon for 100 octane.
or in your case saving $0.30 a gallon to run low instead of premium octane.
 

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That is what i have looked into water/alky injection for, is an effective octane increase or more specifically to eliminate detonation without having to buy expensive high octane fuels.

Yes just to add it to a stock motor without having a need for it, it does nothing for power, just like 100 octane fuel when all you need is 87 Octane is not going to get you more power.

But 100 octane will allow you to crank up your timing or compression thus ending up with more power .

Same with the WI it in and of itself does not add power, it may cool the intake charge a bit, but that can be canceled out by things mentioned above.
But, the WI allows you to turn up your timing, boost, etc that can result in more power, and usually cheaper than $8+ a gallon for 100 octane.
or in your case saving $0.30 a gallon to run low instead of premium octane.
Okay, so say hypothetically. I install water injection on my ride. Then to make use of it I bump my timing at the distributor. What happens when the water isn't spraying? This is the fundamental problem guys. It's not that water won't or can't work. It's that OUR cars do not have an option to account for it. The only way WI will help is in a purpose built car or under the control of stand alone management.
 

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I always though t there were 2 benifits of H2O/meth injection, one being
octane increase, two since liquids can't compress, doesn't in increase compression, slightly?
(Obviously a newb question?)
 

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Okay, so say hypothetically. I install water injection on my ride. Then to make use of it I bump my timing at the distributor. What happens when the water isn't spraying? This is the fundamental problem guys. It's not that water won't or can't work. It's that OUR cars do not have an option to account for it. The only way WI will help is in a purpose built car or under the control of stand alone management.
A car is not going to detonate at idle, it will detonate at high engine load situations.

So you set up the WI to inject when you need it like >50% throttle, or tap into the MAP sensor, or whatever works for your car.

All i know is a bunch of guys use it and run more power than they did without it. On an NA application it is more limited, but it can up the effective octane when needed. The disadvantage would be the risk of running out of water, so spend the extra money for low water level warning lights and flow sensors etc. And if you just add it to an engine that doesn't need it it will lower power

Maybe i am missing something??
 

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Well first off the timing "curve" isn't linear, as the name implies. So you cant just add 2 degrees of advance across the board. Secondly, detonation is MOST likely to occur at lower rpm's and under mid-load. So your on your way up a hill cruising at 60mph, throttle input at 10%, and the engine see's low rpm & high load and starts detonating.

Yes lots of people make mre power on water, if you had a drag only car you could adjust the water to work with the known conditions it will be working under. But for daily driving or fuel economy benefits you need to be able to adjust the timing and fuel to deal with the water when it's on because the situation will be dynamic.

To be clear I am in no way against WI, nor do I see a problem with using it on NA engine. The problem I see is controlling it. If you had a stand alone management system there would be no problem. What I'm saying is "you cant just strap it on and work it out", the other half of the equation is the control.

As in my previous example if you bump the timing for the water at the dizzy. Say you get lucky and find an amount of timing advance that the engine can run without detonating when the water isn't spraying. Does that advance equal the amount of water being sprayed? No, it's just the most advance you could run without beating a rod out of round. What about the fuel? So your spaying water under load, and hoping you can add enough advance to make that a benefit instead of just retarding the ignition event into the stone-age. But now your fuel is too rich because the water spraying is occupying space that should be occupied by air. So you what; turn down the fuel pressure? Now what happens when it's not spraying?

Do you guys get what I mean? You'll just be chasing your tail to infinitum.You HAVE to have control of fuel & spark when it is spraying there's no way around it.

@ Keith Alto; there are no newb questions, just ones you haven't asked yet. The first effect you listed is correct, the second is not. Water in the cylinder will not increase compression (yes I know water is nearly incompressible) the reason being that the water is not in addition to the final static compression ratio of the cylinder but rather removes air from it. So the second effect; is that WI will richen your fuel mixture.
 
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