Water injection improves MPG?

[stovie]

There are two main things that should imho be taken into account in order to get the best results from water injection, and that is cr and lean burn!!

First, with a higher cr you get higher temperatures on the compression stroke which water takes care of and can allow you to drop octane down instead of buying the higher octane.(just make sure to always have the system full!!)

Second, lean burn can be better utilized due to the water again soaking a good amount of the heat from the burning of fuel allowing you to be able to lean out more then 25% in some cases.(from what I understand a ice is running 25% rich in order to keep temps down?!?)

And for a third one, waters rate of expansion is far higher than air is so having some water injected into your engine either way can improve its performance whither its power or fe specifically it's still a benefit in the end(however there's a possibility to get greater benefits when the other two are added to the equation!!)

[teoman]

Have a look at this video series.

https://m.youtube.com/watch?v=RRt50aSjrx4

It is about ecu tuning. There is one about EGR delete. You could delete the EGR and use that signal (and its control loop) for lpg or water injection.

Also please check user Harlan's threads (and his youtube channel Voiding Warranties). He is using a gasoline engine injector to inject water that gets its input signals from the cars canbus.

[teoman]

Also, from my research (no practical experience whatsoever). Lean burn likes a hot intake temperature 85 deg C. (On an hcci engine). Otherwise the lean mix does not burn. That was one of the things i wanted to try with steam injection. I could not find the canbus codes for MB so the project ran out of steam (pun intended). The steam heats up the intake air and condenses in to very fine droplets, these get sucked in to the cylinder and then suck up some of the heat of the lean burn.

[cRiPpLe_rOoStEr]

Originally Posted by stovie

with a higher cr you get higher temperatures on the compression stroke which water takes care of and can allow you to drop octane down instead of buying the higher octane

Maybe it could be more cost-effective to use a lower amount of higher-octane fuel instead of going lower in the octane rating.

waters rate of expansion is far higher than air is so having some water injected into your engine either way can improve its performance whither its power or fe specifically it's still a benefit in the end

I'm not sure to which point it would be so great to add steam, since it's already expanding and would displace some oxygen at the intake tract and decrease the effective compression. Water droplets might be still better in the end, because there is more expansion left to happen inside the cylinders and it may retain more residual heat that would otherwise be wasted through the cylinder walls.

[stovie]

I'm not sure to which point it would be so great to add steam, since it's already expanding and would displace some oxygen at the intake tract and decrease the effective compression. Water droplets might be still better in the end, because there is more expansion left to happen inside the cylinders and it may retain more residual heat that would otherwise be wasted through the cylinder walls.[/QUOTE]

I remember watching a utube video were this guy used a scope camera to look into his intake and exhaust on his car, and the were pretty badly carboned up(I believe it was a early 90's Honda Civic?!?)

He then got one of those portable steamer cleaners with a power inverter in his car to power it, and ran that to his cars intake will it was running. It immediately ran smooth as silk, and he ran it on his car for 2-3 refills(steamer refills!!) and then rescoped the motor and everything looked like it had just come off the factory floor that morning!!

If I remember correctly he also got around 3-5mpg improvement after running the steamer through his car.

[cRiPpLe_rOoStEr]

Originally Posted by stovie

I remember watching a utube video were this guy used a scope camera to look into his intake and exhaust on his car, and the were pretty badly carboned up(I believe it was a early 90's Honda Civic?!?)

He then got one of those portable steamer cleaners with a power inverter in his car to power it, and ran that to his cars intake will it was running. It immediately ran smooth as silk, and he ran it on his car for 2-3 refills(steamer refills!!) and then rescoped the motor and everything looked like it had just come off the factory floor that morning!!

It's usual to see claims that water injection (not steam) on a regular basis decreases noticeably the formation of carbon deposits at the intake manifold, though I haven't seen any claim that it would clean old deposits.

[teoman]

The cleaning aspect also interests me. Especially with these mew diesels and their egr's. However i am a bit worried that all that gunk is going to clog up the cat or dpf.

[teoman]

Originally Posted by cRiPpLe_rOoStEr

Maybe it could be more cost-effective to use a lower amount of higher-octane fuel instead of going lower in the octane rating.




I'm not sure to which point it would be so great to add steam, since it's already expanding and would displace some oxygen at the intake tract and decrease the effective compression. Water droplets might be still better in the end, because there is more expansion left to happen inside the cylinders and it may retain more residual heat that would otherwise be wasted through the cylinder walls.

Well, unless doing direct steam injection, jou cannot really add steam. I fairly wuickly heats up the air and becomes droplets.

Have a look at your kettle boiling. The steam is transparent. If you can see it, it is liquid droplets suspended in the air.

[cRiPpLe_rOoStEr]

Finding room for a steam injector in the cylinder head would be quite challenging. When it comes to the cleaning effect, it would be supposed to not lead to DPF clogging, since the steam solubilizes those carbon deposits in order to enable them to be burned.

[ctmaybury@yahoo.com]

If we go back to straight water injection for a minute and let the combustion temp create the steam. How much pressure would you need for good atomization? Would 100 psi wih a decent nozzle do the job? With my lpg now, I don't need a pump. I use a bbq regulator and an orifice from my stove conversion. Hobbs switches trigger solinoid valves to give me stages (3 stages at 5 psi intervals now, soon to be 5 or 6 stages). I would think stages would be a good idea with the water too. I fumigate the lpg before the turbo on the suction side. I think with water, I'd prefer to inject it after the turbo. My boost goes from 0 to about 32 psi at wot. 100 psi should be plenty to inject it into a 30 psi stream. 200 psi might get better atomization though.