|
Water Injection 2008
Since the last thread that attempted to explain the aspects water injection turned into a shitstorm, I've decided to draw up a new one.
There seems to be a bit of confusion of what the actual benefits of water injection are, essentially by introducing extra mols of Oxygen to the combustion reaction in an engine you are effectively raising the level of energy (heat) needed to react the components, which allows you to compress more gas (producing heat) without having the mixture ignite at the improper time, (better known as detonation). The easy way to express this is to say that adding Oxygen effectively raises the detonation threshold Just to be clear, a combustion reaction is an endothermic exothermic reaction in which a chemical reacts with Oxygen and produces heat so rapidly that a flame ensues (ignition phenomena). The fact that water has a high specific heat capacity would seem to insinuate that the intake temperatures will noticeably drop resulting in a denser charge and more power being had at the same pressure level. You'd assume this is true because the required energy to vaporize the injected water droplets would be pulled from the surrounding heated gas, this being a very hot topic in the last thread. The simple fact is that on your average boost setup (<~15lbs) the temperature differential simply isn't high enough to vaporize all, if any, of the water before it reaches the combustion chamber. While it is going to cool the charge, that isn't the main reason the knock limit is raised. Something with a much lower boiling point, Alcohol, Nitromethanol, Nitrous Oxide, would be a better alternative for dissipating heat from the intake charge, not to mention all three add chemical potential energy to the intake charge (Alcohol and Nitromethanol both have strong chemical bonds, and NO2 has, hey look at that, two Oxygen molecules tacked onto it.) To address some of the more common questions I've seen, my reply to Schwitzer Turbo's post:
Originally Posted by Schwitzer Turbo
PS: i do care how it works now its time to make the power....
so what would be the Best way to impliment this into my setup as my setup has already come so far. if im boosting 1.5 bar on pump with meth whould it be theoretical for me to boost 2.5 bars? who else has gone into the field and come buck with results. and does timing kill motor's? is there alot of power in advancing timing? cos what i have been told is that it safe to boost more with conservitive timing than to any advance timing?
Originally Posted by wafflesincars
------- christ.
You are putting the cart before the horse. The addition of water and methanol makes it harder to bond hexane molecules with oxygen (ignition phenomena) because there is more mols of given the given gas, and the chemical bonds in propyl molecules are "stronger" than a hexane. Advanced timing is only good for power if you can utilize it to explode more gas at a desireable piston position, i.e. when a surge of expanding gas would translate into kinetic energy, like when the piston has just begun to descend; the most desriable would be total combustion by mid-stroke. In an N/A motor to achieve better combustion you would advance the timing so the air/fuel mixture would ignite before the piston is at TDC (the piston will still be compressing the gas, gas isn't fully compressed- requires less current to light, once ignited compressed molecules will propagate more quickly than if the piston was decending) hence when you are checking timing you want it to be around 15o before TDC (Honda), for proper combustion. Now with a boosted motor you have much more gas occupying the cylinder than you would with an N/A motor. Which is why as the amount of gas (pressure units) increases you want to retard the timing, the molecules are closer together and will propagate flame more quickly, too advanced and you are going going to have full combustion at the wrong piston position (oh noes for your rods, pistons, and sometimes the block; on occasion all three, but the weakest link tends to go first.) This is why tuning ignition timing is deemed a bit trickier than A/F, you want to get maximum flame propagation (exploding all that chemical potential energy is a good thing) without destroying your engine. This is where A/F tuning and ignition tuning get a bit more interelated, as per usual you tune the A/F first, this is smart because then you can tune the timing for whichever A/F ratio you have established, but "tuning A/F for power" incurs running the most efficient (usually leaner, but there is diminishing returns) ratio you can without getting dastardly preignition (having the mixture ignite prematurely,essentially the same as too far advanced timing but it is spontaneous, piston comes up while gas is pushing down; ask Fred and JD, I'm sure they're both very familiar with exploding too quickly) Now a leaner burn will require less advance to combust entirely. Why? Because there is less reactant (fuel), to burn (react with oxygen) so less time is required for a complete reaction to occur, which essentially translates to more efficient power; add more fuel and air in the same increments and you will have more power. Now with a richer mixture you could further advance the timing because there is more reactant to burn, in most cases this is inefficient, but this is why old carbureted, power valve added, vacuum advanced, contact point V8's are so ------- badass. When the engine is at a high rpm there is more vacuum, a specific resistance spring mechanism allows the timing to be advanced accordingly and the big ------- carb + extra valve for increased airflow (higher vacuum venturi) gives you massive amounts of ridiculousity (HOSPOWAH). What water injection allows you to do is add more molecules of Oxygen to the mixture, essentially raising the "octane rating" of the fuel, the more molecules of reactant the longer the reaction will take, the less preignition/detonation you will have (detonation occurs when the fuel mixture ignites spontaneously at random intervals due to heat, usually collections of matter with different thermal properties than the rest of the metal cause "hotspots"; carbon deposits built up over time are the most common). The introduction of a molecule with a high specific heat capacity also keeps ignition temps reasonable, versus a lean mixture which will incur more heat (less fuel to react and carry away the heat). The reason that Methanol injection is so nice is for essentially the same reason, propylene molecules have strong chemical bonds, which translates to a high chemical potential energy (lots of energy is released when the bonds are broken) so effectively it requires much more energy to break the bond (heat) and the A/F mixture will not explode as easily as gasoline alone (which has weaker bonds, requires less heat to ignite = preignition and detonation at lower heat levels). These effectively raise the threshold for detonation, or the knock limit (knocking is the sound of preignition, rod knock, piston slap, and other mechanical maladies are coined thusly because of the similar sound *clack*clack*pop*I'm dying*clack*) which translates to you being able to shove more gas into your engine without it exploding at the wrong time, which usually equates to massive amounts of ridiculousity (B000Stt y0!) This is why nobody has come back with "results", because it isn't a "bolt-on" matter. Now if JD would please pull his dick out of Fred's ass, I'd like to make another thread that has strictly NO BULLSHIT and only accurate details pertaining to the subject because this is a viable means of making more power for cheap. http://users.frii.com/maphill/wi.html This site helps you get a handle on how to tune your car, as you will need to take advantage of that new higher detonation threshold: http://www.importbuilders.com/tuningacar.htm This site is where you will go before you post a reply with a question in it: www.google.com Please try to keep this thread free of bullshit posts, if you start shitting up the thread I will pull a Bitchy McWhineypants and pm a moderator, even though it's futile, and imminent, it's going to happen. Feel free to add whatever you feel would be constructive to the thread, even though the basics (all you really need to know) are extremely straightforward. *More stuff from the last thread: https://www.homemadeturbo.com/forum/...?topic=48057.0 http://www.angelfire.com/super/buickgn/index.html http://users.frii.com/maphill/wi.html http://www.imoc.co.uk/technical/article/wi.htm JD on pgmfi (don't know if it's back up): http://forum.pgmfi.org/viewtopic.php?t=4055 http://forum.pgmfi.org/viewtopic.php?t=6523 |
Re: Water Injection 2008
make sticky...
|
Re: Water Injection 2008
jd doesnt approve of this thread :P
|
Re: Water Injection 2008
Originally Posted by ososlohatch
jd doesnt approve of this thread :P
|
Re: Water Injection 2008
Originally Posted by ososlohatch
jd doesnt approve of this thread :P
|
Re: Water Injection 2008
*Oh and to add for people who looked at the "How-to" link and where confused by him stating outright that water injection effectively lowers the intake charge.
He's talking about it being used on aircraft, where the water would vaporize (boil) at a much lower temperature because of the pressure being much lower at high altitude. pV=nRT Where, p= Absolute Pressure in Pascals V= Volume in meters cubed; m3 n= Number of Mols of substance; the amount R= R is the gas constant (8.314472 m3*Pa*K-1*mol-1); which needs to be memorized/ written down. T= Temperature in Kelvin |
Re: Water Injection 2008
Don't know what aircraft engined you're refering to but, water injection on gas turbine engines is used during take off. At ground level.
|
Re: Water Injection 2008
Originally Posted by absolutezroo
Don't know what aircraft engined you're refering to but, water injection on gas turbine engines is used during take off. At ground level.
P-51's my grand-pappy flew, and most old turbine FI motors run the water injection next to all the time, especially with that terribly inefficient, yet compact, allison s/c. ;) Of course on the P-38's, which used turbochargers, were also water-injected, as were all of the high altitude aircraft in the Air Force/Navy fleet; but gee, I wonder why? I never said they turned it on specifically at high altitudes, as the benefits gained are the same as you'd see in your Civic, at take off, at ground level; but that's where significant drops in IAT would be noted, at high altitude. Because there's less pressure. |
Re: Water Injection 2008
Originally Posted by Joseph Davis
------- fist yourself, Fred.
|
Re: Water Injection 2008
Originally Posted by Toysrme
JD ftw JD and Fred can go play swordfight in another thread. :3 |
Re: Water Injection 2008
Originally Posted by fe3tcourier
and take his sack out of your mouth too.
classic |
Re: Water Injection 2008
Originally Posted by bitchasscracker
classic |
Re: Water Injection 2008
Originally Posted by wafflesincars
Please refrain from useless dick-swinging.
JD and Fred can go play swordfight in another thread. :3 lmao |
Re: Water Injection 2008
Originally Posted by Toysrme
JD can tounge lash anyone, anytime he feels like it.
lmao |
Re: Water Injection 2008
you have waffle in your name...
|
Re: Water Injection 2008
Originally Posted by Toysrme
you have waffle in your name...
I get stormed by belgians on a daily basis. You'd think they'd have the dignity to leave it off of my birth certificate. :3 |
Re: Water Injection 2008
firstly, to all the other posts : LOL
Originally Posted by wafflesincars
but that's where significant drops in IAT would be noted, at high altitude. Because there's less pressure.
did i miss something? |
Re: Water Injection 2008
wouldn't make a rat's ass if it did drop the iat's. this aint home made turbine powered pressurized aircraft.com
speaking of which... noone has done a turbo->turbine project here? i would, but i enjoy what little hearing i have left hah |
Re: Water Injection 2008
http://i50.photobucket.com/albums/f3...ag-by-fred.png
i dunno, but someone build this! i'm keen to see how it goes. sure its bulky and heavy and complex, but it should make full boost always if setup right. |
Re: Water Injection 2008
Originally Posted by fe3tcourier
firstly, to all the other posts : LOL
why? it seems to me that inside the closed system that is a boosted intake charge pipe, boost is boost is boost, the contents of said pipe do not know or care that they are in a vacuum or at 10000 leagues under the sea. the only difference is in the compression done by the turbo to achieve those pressures because of the thin air and associated extra heating. if its 10psi its 10psi (that is above 100kpa, not outside base). did i miss something? But yea if it was sprayed in the charge pipes as per usual the pressure it would see would be the same, but the lower density of the charge allows the water to vaporize according to Gibbs free energy law where the energy of a gas is directly proportional to it's distance of travel, or obit. Stop shitting in the thread. :3 |
Re: Water Injection 2008
What's the problem here?
|
Re: Water Injection 2008
Originally Posted by bluerex
What's the problem here?
|
Re: Water Injection 2008
Cool I got a sticky. :P
|
Re: Water Injection 2008
a little repetitive but overall a nice write up. good job. now we need some actual tuned numbers. preferably tuned before adding, then tuned after adding to see what kind of power you made.
|
Re: Water Injection 2008
|
Re: Water Injection 2008
Why do all the nig-nogs have to ---- on perfectly sound, albeit (that means 'although', cocksuckers) uncommon ideas not used in OUR community?
Although using just water isn't all that helpful with low IAT's, using a mix of methanol+water helps regardless. Methanol supplies both fuel and oxygen, as well as boosts octane. Methanol helps makes more power at any psi/iat due to the fuel & octane aspect. Most cars at the limit of their fuel run 50/50 mix, and all you need is the -25F washer fluid (40% meth) for a cheap mix. I was actually reading everything on the Devilsown website (sell progressive injection controllers/kits), and everything there supports the evidence that meth works, but works best only when your setup is maxing out due to something (usually gas or turbo). FWIW, my friend's Evo 8 used to make mid 400's (iirc it was 437awhp) with a stock turbo, and the only mods were increased boost, a better tune, a clipped turbine, and Meth Injection. He has a 55gal drum of methanol sitting at his mom's house. I can't get you dyno sheets, since his car just came back from some place in Chicago or Ohio, and past 600awhp with the new gt35 & ----. |
Re: Water Injection 2008
Originally Posted by HiProfile
Why do all the nig-nogs have to ---- on perfectly sound, albeit (that means 'although', cocksuckers) uncommon ideas not used in OUR community?
Although using just water isn't all that helpful with low IAT's, using a mix of methanol+water helps regardless. Methanol supplies both fuel and oxygen, as well as boosts octane. Methanol helps makes more power at any psi/iat due to the fuel & octane aspect. Most cars at the limit of their fuel run 50/50 mix, and all you need is the -25F washer fluid (40% meth) for a cheap mix. I was actually reading everything on the Devilsown website (sell progressive injection controllers/kits), and everything there supports the evidence that meth works, but works best only when your setup is maxing out due to something (usually gas or turbo). FWIW, my friend's Evo 8 used to make mid 400's (iirc it was 437awhp) with a stock turbo, and the only mods were increased boost, a better tune, a clipped turbine, and Meth Injection. He has a 55gal drum of methanol sitting at his mom's house. I can't get you dyno sheets, since his car just came back from some place in Chicago or Ohio, and past 600awhp with the new gt35 & ----. Nobody shat on anything, except the thread I was trying to keep clean, in that they want to know what "works". Yes meth works by adding thermochemical potentia, as does water, I just explained why. I really wanted someone to step up and be like, "I don't know what ya'll's problem is, squirting water and methanol will yield power returns, my buddy's car made x amount with this and x amount of this with this, this, and this done." No ----. The more energy required to explode the fuel the more heat energy you can throw at it.
Originally Posted by HiProfile
my friend's Evo 8 used to make mid 400's (iirc it was 437awhp) with a stock turbo, and the only mods were increased boost, a better tune, a clipped turbine, and Meth Injection.
But that's neither here nor there, our "community" happens to be more power, or faster, for cheap. No one else on here gives a ---- about being an import elitist, because we know imports fail anyway, they are simply cost effective- sometimes. |
Re: Water Injection 2008
This is a fairly good discussion of the practical setup side of it :
http://forums.evolutionm.net/showthread.php?t=292953 the only ones i would consider are PWM and port PWM, preferably the latter driven from the injector channels for a good fuel:water ratio at all times. |
Re: Water Injection 2008
http://www.rbracing-rsr.com/waterinjection.html
A bloody load of really good, yet redundant with respect to the cases presented here, information. Seriously there is a lot of ---- to read on that page. *Ninja edit: That ------- site has everything you'd ever need to know about water injection and a good bit about engines in general. Oh, and for you piffy fools who want some kind of magic numbers there's a calculator at the bottom of the page to do all your work for you, well practically. |
Re: Water Injection 2008
water injection is the S*** 3 years of ultra abuse on my rotary and still perfect... KNOCK OWNED :y
|
Re: Water Injection 2008
Originally Posted by Zriuz
water injection is the S*** 3 years of ultra abuse on my rotary and still perfect... KNOCK OWNED :y
Oh, and you don't have to censor yourself, at least you didn't have to previously. I don't know if Xeno Nazi-fied the word filter yet. |
Re: Water Injection 2008
word filter check
---- edit: nope no word filter |
Re: Water Injection 2008
PS Blew my motor on water/meths Maiden Voyage @ 2.2 bars.
Rebuilding then will get back to you guys, watch this space... PS: The motor was already fucked,, and had slight blow by already it was 30 Degress outside and the car was already sitting in the RED, but it felt so darn Good........ Next thing oil on the windscreen.... |
Re: Water Injection 2008
::)
|
Re: Water Injection 2008
I drove the car around for about 2 weeks on Just water. then I increased boost with water meth to 1.8 bars did 100 miles in it. then we took it on the road for a Big HP tune. Insert Oil Splat here. anyway I have only got myself to blame...
|
Re: Water Injection 2008
I was reading up on water/meth injection...lamans terms said that as water was injected into the system post-turbo and inducted into the motor, it would evaporate once inside the combustion chamber, taking away extra heat--hence added cooling.
The methanol part is used as a detonation preventative (raises octane) so that you could advance timing more for extra tunage. I've heard that windshield wiper fluid works great as long as you dont use the glycol based fluid. |
Re: Water Injection 2008
Originally Posted by schim187
I was reading up on water/meth injection...lamans terms said that as water was injected into the system post-turbo and inducted into the motor, it would evaporate once inside the combustion chamber, taking away extra heat--hence added cooling.
The methanol part is used as a detonation preventative (raises octane) so that you could advance timing more for extra tunage. I've heard that windshield wiper fluid works great as long as you dont use the glycol based fluid. The water vaporizes, it never evaporates, i.e. it enters as water and in the combustion reaction gets split into Hydrogen and Oxygen separately, it reforms with excess molecules later. There is some amount of heat absorbed, but it's there for effectively the same reason the alcohol is, raising the octane. Windshield washer fluid is water and methanol/some kind of propylene molecule. But yea, this thread shouldn't stay here. |
Re: Water Injection 2008
Originally Posted by wafflesincars
There seems to be a bit of confusion of what the actual benefits of water injection are, essentially by introducing extra mols of Oxygen to the combustion reaction in an engine you are effectively raising the level of energy (heat) needed to react the components, which allows you to compress more gas (producing heat) without having the mixture ignite at the improper time, (better known as detonation).
The easy way to express this is to say that adding Oxygen effectively raises the detonation threshold...... .........What water injection allows you to do is add more molecules of Oxygen to the mixture, essentially raising the "octane rating" of the fuel, the more molecules of reactant the longer the reaction will take, the less preignition/detonation you will have (detonation occurs when the fuel mixture ignites spontaneously at random intervals due to heat, usually collections of matter with different thermal properties than the rest of the metal cause "hotspots"; carbon deposits built up over time are the most common). The introduction of a molecule with a high specific heat capacity also keeps ignition temps reasonable, versus a lean mixture which will incur more heat (less fuel to react and carry away the heat)....... ........o, water is an oxidation agent as well, it's highly reactive, especially in a combustion reaction where there is so much heat. The water vaporizes, it never evaporates, i.e. it enters as water and in the combustion reaction gets split into Hydrogen and Oxygen separately, it reforms with excess molecules later. There is some amount of heat absorbed, but it's there for effectively the same reason the alcohol is, raising the octane... In simple terms, the water goes through a phase change during the compression stroke, which removes a significant amount of heat from the charge, suppressing detonation. In turn, you can now effectively increase boost to add more oxygen. |
Re: Water Injection 2008
Originally Posted by patsmx5
For the most part I agree with everything you've said, but this part not so. Are you saying that spraying water in the motor adds oxygen? Or are you saying it will suppress detonation and allow you to add more oxygen to make more power? I'll agree with the later. I think that's what your saying, but it's wordy at best. No, now I see you do say it's an oxidizer in a combustion event. How so? I don't think that's correct. If it did, then the hydrogen would react with the oxygen. If that were so, then we could simply spray LOTS of water in the motor with just enough fuel to get the reaction going. In this case we wouldn't need a turbocharger at all, just gas and air to get the reaction going to burn the water.
In simple terms, the water goes through a phase change during the compression stroke, which removes a significant amount of heat from the charge, suppressing detonation. In turn, you can now effectively increase boost to add more oxygen. The presence of hydroxides and hydrogen ions is what really enhances deflagration and ups the required activation energy of the reaction. As far as being able to burn the water I think you're neglecting stoichiometric ratio for the charge you're putting into the cylinder, there still has to be enough heat and ionized hydrocarbons to get the water to dissociate in order for it to "burn" properly. A large amount of activation energy is required to have the water enter a transition state as well, liquid water doesn't burn. Essentially water is somewhat of a catalyst that raises the amount of heat you can throw at the charge before it ignites, as well as raising the density of the charge overall just by evaporation (lower heat levels). I'm going to go tend to my hangover now. |
Re: Water Injection 2008
so nobody still has numbers to look at what kind of gains were actually dealing with as far as meth/water and water
|
| All times are GMT -5. The time now is 03:21 PM. |
© 2024 MH Sub I, LLC dba Internet Brands