[boostednut]

Methanol has a lower latent heat per volume than water which has the highest latent heat of all fluids, several times greater than methanol.

Meaning the amount of energy needed to turn methanol fluid (in the form of droplets in your intake) to gas, is much lower. That change from fluid to gas is what lowers the temps.

In car world, your AIT are between ambient for NA roughly, and like 120~ (hopefully never higher than that). Regardless the exact temperature of your intake air temp, it's not nearly high enough to turn water into steam. So methanol is much better at lowering intake temps than water.

But that phase changed methanol is still flammable so it burns when it gets in the combustion chamber (under spark). The next part is the one thing people don't recognize. Methanol molecule actually has oxygen it releases during combustion. Not a lot of oxygen, but enough to add oxygen to the burn. Ends up putting out a bit of water I believe after chemical reactions resulting from the burn. More oxygen means more power.

Water on the other hand stays mostly a liquid (droplet) until it gets in the combustion chamber, where it will do most of it's phase change (energy absorption) during the flame front propagation. The cool thing about water is it doesn't put out the flame at all. You should know this in case your shit ever catches on fire; don't fight any kind of meth/gasoline/ethanol fire with water. It won't do shit. It will only likely push the fuel out in different directions and give you a worse situation.

The thing about water is that it helps cool the combustion process and meth cools the intake process. Two different properties linked to the natural properties of both. Meth is inherently a lot easier to tune with. About 1000x easier. Fuel her up, throw some timing with colder IAT and a bit higher octane, and there you go, easy power. VS water is a lot more nuanced. You need to use EGT to find a threshold for how much water to add, and how much timing to add. Because with water you can easily pull too much heat out of the cylinder. But that being said, water is a lot safer. In theory and in practice it curbs detonation like a mofo.


So with those things being said, for an LT1, which has weak rings and real high DCR and SCR, I would not turn my nose to a 50/50 mix. Water might not get you as much power as 100% meth, but will surely help keep those in cylinder temps down.

An extra 20whp vs potentially keeping that engine alive a lot longer. I think I'd settle for a bet of extra guarantee in case I get a bad tank of gas.

Also FWIW, this started on old turbo charged war planes. And they found that ultimately the most power was made with water injection. Those systems are a bit different than a DI v8 with a blower, but it's worth noting. They just crammed more fuel, more air, and then water to keep it under control. Water also works wonders with nitrous. Run a couple step colder plugs, add some water and you can crank the gas up.

Another thing to note, if you're spraying pre impeller/blower/turbo whatever, don't do it with water. Only do 100% meth or alcohol. Water in theory will pit the blades over time, while meth etc will evaporate into gas much quicker, much less likely to damage high speed parts. In either case ask your manufacturer if it's safe to spray. Some blowers can get their rotors eaten up over time with meth. Most of the time it's fine however.