I don't post here often, but I'm going to do it on this thread. I am doing so to clear up some errors and misinformation, not to hurt your feelings. That said, this is going to be a massive e-beating, because there is a lot of nonsense being spouted here and you need to stop it. Get your Nomex jammies on and prepare for a massive pick-apart.
My first comment is this: water injection will not do squat, on the road or off, for a typical naturally aspirated 22R. If you believe me on that, great - skip the rest. If you don't believe me (and, if you don't know me, you shouldn't just believe everything you read) then read on and I will explain why.
if you have a carburetor that can do it you can also water inject it
Ignoring for a moment the fact that the first step in getting usable power from a carbureted 22R is ditching the carburetor in favor of fuel injection, water injection has
nothing to do with "having a carburetor that can do it" because there's not an automotive carburetor alive that has built-in water injection!
that will bring up compression a lot.
It most certainly will not.
Static compression ratio is a simple mathematical issue of volumetric proportion. In shorter words, it's a matter of how big some things in the motor is compared to how big some other things is.
Dynamic compression is affected by the static compression ratio as well as valve timing, engine speed, temperatures, manifold absolute pressure, etc etc and could be influenced by water injection if you were spraying
massive amounts of water - which you wouldn't, because there is no benefit to it on a timid forklift engine like a stock 22R.
unfortunately it costs you the life time of the engine which will be a lot shorter.
Absolutely not true. Assuming that you spray
reasonable amounts of water, engine life would not be decreased. If you choose to spray
unreasonable amounts of water, you will get the results you earn - chiefly, failure!
same thing with advancing your timing, it gives you more power and better gas mileage
Whoa, whoa, hold up there, Ace. You are making the assumption that the stock spark advance curve can be improved across the board by moving the entire curve forward by an equal amount. While there may be
some improvement to be had by advancing timing a couple of degrees, it is typically not universal. A better place to start is by rebuilding the distributor, making sure that the mechanical and vacuum advance mechanisms both work properly. Neither of those should be assumed on anything old enough to have mechanical and/or vacuum advance distributors.
but if you do it too far its harder to start your engine and burning too much before tdc you can end up damaging the head and/or the pistons
This (or some portion of this) I will agree with: If you run more spark advance than your engine can handle, it will detonate, and you will get the results you earn - chiefly, failure!
when you water inject an engine it significantly cools the fuel/air mixture
Well, not exactly. Water has a very high specific heat. In other words it can absorb a lot of heat without raising its own temperature, compared to other materials. When a fine mist of water is introduced to a piston engine's combustion process, it can remove a lot of heat from the cylinder without putting out the fire. This act - removing heat - is what helps eliminate detonation.
which allows it to be compressed more than normally
Well, sort of. Eliminating detonation allows more dynamic compression. However, injecting water does not change the engine's compression ratio.
which boosts the power out put
Again, only sort of. If you are running stupid amounts of boost and need to eliminate detonation, water can help, and that will boost power. However, spraying water into a dog-eared 22R
will not increase compression; seeing as there should be no detonation without the water, spraying water
will not eliminate detonation that does not exist; and thus
will not increase power.
while also making it less likely to detonate prematurely on the next cycle.
Again, if it is properly tuned, a stockish 22R should be nowhere near detonation even without water. You are solving a problem that you don't actually have.
The down side is that you can only water inject when the engine is at full throttle and wide open or you run the chance of drowning out your pistons by flooding them with water.
Seeing as water injection only provides benefits under load, there is simply no point in spraying it at any other time. And again, any reasonable volume of water, sprayed under load, would not damage the engine. You can run far more water than the engine can use, and it will give you fair warning by temporarily running rough and losing power long before it checks out. Been there, done that, printed the T-shirts, sold the movie rights long ago.
The other way that it can hurt your engine is that when the water droplets take on the heat of the combustion the resulting steam cranks up the pressure in your cylinders (basically turning heat into pressure)
Ahhh...well, no. Yes and no, actually. In theory, the elimination of detonation (again,
solving a problem that you shouldn't even have) brings peak cylinder pressures down. In practice, you may also see an increase in BMEP (look it up) as the water flashes to steam. However, because so much heat is removed from combustion, you get more average pressure and lower peak pressure. That means a longer, gentler push on the piston, without the violence that high temperatures brings. That is a VERY good thing, because it makes
more power with
less stress on internal components.
which your standard engine won't be able to take for very long.
Incorrect - unless you can show me an engine that lives longer under short, sharp, violent, blistering hot combustion events than it does under longer, cooler, gentler ones.
it is a great concept and helps a lot with fuel economy, boosted power output, and cooling of the engine,
Only if you are running pisswater fuel that cannot accommodate the staggering high compression ratio of a 22R, or running higher dynamic compression and/or more spark advance than your fuel warrants. The cooling comment is correct, but only if the engine is running outside the parameters of the cooling system (which indicates, no surprise here, a failing cooling system) or one of both of the two conditions above are being experienced.
but it greatly increases the amount of pressure that your engine has to deal with
Technically correct answer: "Only sort of, maybe". Practical answer: "No." See three paragraphs up.
i actually found this out talking to my mechanical genius of a grandpa
Be careful now. With all respect due our elders, he may or may not be a genius. The facts that he is a) old and b) related to you do not make him automatically intelligent
nor automatically correct. It also does not guarantee that he is telling you the truth, or even that he remembers the truth in its entirety. And certainly there is no guarantee that you understand it fully. If you do not understand it fully, as seems to be the case, I am willing to bet significant sums of money that you are unable to even repeat it as he told it to you.
then looked into it a little bit more just surfing the web,
Caution is warranted here. There is no better way to find every idiot in the world than to give everyone a computer and internet access, assure them anonymity, assign zero consequence for their actions, and turn them loose on an audience of infinite followers hanging on every word.
a lot of the things i found tho were for supercharger/turbocharger application because it looks like they're used to help with cooling on those systems
Bingo. Why? Because turbo/SC applications have huge inlet temperatures, huge combustion temperatures, and huge peak combustion pressures. Water injection can address all three of those conditions with no ill effects, and can do it for pennies.
I think ive heard of them using water injection on old military trucks back in the day to get a little extra power out of them.
I suspect it's not trucks, but planes you read about. Water injection was a major player in getting
huge power out of military aircraft in WWII. Check out this 2800 cubic inch badass - 18 cylinders, turbocharged, water injected, and generally built out of solid, 99.4% pure awesome:
http://en.wikipedia.org/wiki/Pratt_&_Whitney_R-2800i'm not saying its a bad idea, just that if you want to try it i'd replace the standard head gasket, advance your timing, and only run premium gasoline
No no no. If you want to try it,
first have a reason to try it. Have a problem to solve. A mild 22R simply does not have the problems that water injection solves. Advancing the ignition timing until you find detonation is absolutely not the way to find the best timing for optimum power. And advancing the ignition just to cause detonation,so that you can then quench detonation with water injection is like stabbing yourself in the hand so that you can put on a Band-Aid. Finally, as I said above, water injection acts as an anti-detonant. That means that you might get away with
lower octane fuel than you would without water. It does not mean that you need higher octane fuel than you would without water injection.
Moral to the story: For the good of those unlucky enough to read what you write, either know what you are talking about, or don't talk about it.
Can I go to bed now?
