Is Propane or water/MEOH Injection worthwhile?
 

I have read some of the ad copy in Diesel Power mag and online that propane injection can get you large gains in economy, in the range of 26 MPG. I presently get in the 16-17 MPG range with my truck on straight #2.

I have also read information from Banks that the claims of diesels only burning 75-80% of the fuel may be true for older IDI engines but that modern engines with their better fuel pumps, higher fuel pressures, improved injectors and computer management systems are much more efficient than that. They also theorize that some of the economy gain associated with propane injection may be coming from the larger exhaust systems that are recommended when propane injection systems are used.

I have read at least one member's post that he uses propane injection for extra power but I guess he doesn't drive in a manner that he would get the higher mileage.

Does anyone out there use propane injection and if so what kind of mileage are you getting with it? I did some number crunching, and at a ratio of 20% propane (1:4) and a cost of $4.00/gal. propane(worst case) and $3.00/gal #2 you would still come out ahead on fuel costs. This assumes 16 MPG straight #2 and 25 MPG with propane injection.

$4+$12=$16 5galX25MPG=125mi. $16/125mi=$.128/mi or 12.8 cents a mile
5gal #2=$15 5galX16MPG=80mi $15/80mi=$.1875/mi or 18.75 cents a mile

It just seems to me like the entire trucking industry would be using propane injection if they could save somewhere on the order of 30% on fuel costs by doing this.

On the other hand, I have not yet found information on water/methanol injection making economy claims. Mostly it seems it is for cooler EGTs and more power. Does anyone have any input on either of these systems?

A guy on the other forum Im on blew apart his with propane. Its expensive but there are alternatives to that kind of spendature.

you have other options and much cheaper...
checkout water4gas.com/trucks.htm

That is possible but you really have to be injecting way to much propane to do it.

You will NOT get that kind of milage increase unless you are using dangerous amounts of propane.
I have been running propane injection for 5 years. I use the Powershot 2000 vapor phase system, one of the safest systems available. My goal was to increase power when towing my fiver and it does that well, I usually dont turn it on when running empty because I dont need the extra power my chip set on performance gives me all I need then. I did run propane all the time when I first got the system and got about 2 mpg increase, the fuel savings was more than made up for by the cost of propane. The Powershot system with a storage tank will runn you better than $1000 so if your are going to try to save money with propane you wont.

I was considering water injection for its cleaning properties. I have read one of the problems with using VO fuels is it causing buildup on valves and rings. Wouldn't water injection help prevent the buildup on the valves and rings? Could use meoh/h2o mix, but for my purposes the meoh would just be for winter as an antifreeze additive. The cooling effect of the water causing the air to be denser is the main goal.. more air in the cylinder allows you to get more power out.

Setting up water injection can be pretty simple and cost effective, depending on how you want to do it. I was thinking of getting a new (I would want to be certain of atomization) nozzle from snow (what size/volume for the 7.3L IDI diesel with a Banks sidewinder? I posted on snows forum and the tech who replied didn't know.) Pull a fuel pump off a F150 EFI (stainless steel high pressure pump) from pickNpull for $20. For controlling it, a toggle switch to switch on when wanted would work, could also use a reostat to be able to adjust the rate as well. IF I was building a racecar I would get a controller that automatically adjusts to the air flow, but I am not. It seems like it would be pretty straight forward, I just haven't had the time or a place to work on it... and I keep having other little things to fix... I have a Banks sidewinder that I need to install too... maybe I will do it at the same time.

I would be very careful using any kind of combustion enhancement while burning VO.
All of the systems are designed for use with #2 and probably would work with BD but VO is a completely different matter. It is much more viscous, molecular weight at least 3 times that of #2 or BD, and it is much more hydrophobic.
You could easily compound the problems already associated with VO.

Phydeaux... Interesting thought... I am not sure what difference it would make. My understanding of water injection is that you are adding water vapor, it would be kin to higher humidity climate, not injecting fluid water in the cylinder. If you are getting water drops then you aren't getting good atomization or have too much volume. I haven't seen any studies comparing humid climates to dry climates? But in the cylinder you have a very hot and controlled environment so I don't think it would be very significant difference. Water injection is nothing new. Taking apart a engine with water injection was always a treat because they were always so clean inside (although the last time I did that was in the 80's). I also hear that engines run with acetone added to the fuel are very clean inside too.

I don't know if I will get around to experimenting with water injection.. but I keep considering it. One of those things that you keep on the list of things to do, but always down toward the bottom...

Instead of running WVO why not make it into BioDiesel then you solve the problem