adding additional diesel fuel via additional injector?

[dansvan]

Ok bear with me. Many have/are using propane injection to increase horsepower. Some have said it acts as a catalyst for the diesel fuel, however I have found no proof of this. I think it's just additional fuel being burned. which leads me to my question. What do you think about adding an additional injector, 12 volt auto style, with it's own high pressure pump and controlled via a boost switch. I understand that a diesel operates by diesel injected under high pressure at a precise moment. However propane is not injected like that. I know a gasoline injector cannot atomize diesel like a diesel injector can, but they can do a pretty good job. Think DPS injectors = stream. So will adding fuel straight into the intake under boost cause things to go boom?

 

[Alex S]

Bad idea!, no control of timing you kinda have to think the IP as a carburettor and distributer all lumped into one

 

[Andylad13]

Diesel fuel into the intake is probably not a good idea because you wont have more oxygen to use the fuel with. You'll just be over-fueling at best. That is "if" you could even light off the cylinder with the additional non-atomized fuel.

 

[dansvan]

You have no control of timing with propane which is an additional fuel as well. As for more air, in our hypothetical situation we are using a turbo to add extra air.

I'm sure pullers etc. would have done this long ago, or maybe are currently, dont live in that world) and am curious what they have found.

 

[Alex S]

yea your correct but propane has an octane rating of 110 there for you can compress it a whole lot without self ignition. where diesel will

 

[19jackal90]

why go through the trouble of engineering a whole integrated system when u could jus engineer a couple heads 4v per cylinder with direct injection and a v8 cat ip or international's 9l v8 inline ip ?
ive tryd injecting diesel striaght through the filter lid on my truck with 60 psi fuel pump lets jus say it didnt sound to good.... snap!, crackle!, pop!, im jus stickin with my water/methanol injection. posibly propane although i kno a guy whos truck got addicted to it and dosent give him anymore power after a week of racing with it.

 

[dansvan]

yea your correct but propane has an octane rating of 110 there for you can compress it a whole lot without self ignition. where diesel will

What are you trying to say?

 

[dansvan]

why go through the trouble of engineering a whole integrated system when u could jus engineer a couple heads 4v per cylinder with direct injection and a v8 cat ip or international's 9l v8 inline ip ?
ive tryd injecting diesel striaght through the filter lid on my truck with 60 psi fuel pump lets jus say it didnt sound to good.... snap!, crackle!, pop!, im jus stickin with my water/methanol injection. posibly propane although i kno a guy whos truck got addicted to it and dosent give him anymore power after a week of racing with it.

I dont want to engineer a different engine. What injector did you use? What pump? Activation? Injecting through your filter lid assumes NA. I'm interested in pressurized applications. I've added adittional injectors on boosted gas apps and have an electronic additional injector controller laying around. I want to know why it wont work not just that it wont. All the air and fuel are compressed into the same spot so I'm assuming its timing.

 

[jhnlennon]

Considering that all the cylinders are firing at dif times, I dont see how injecting diesel into the intake would work, there would be no way to meter the fuel to all the cylinders when they need them. The propane only acts as a accelerant. Propane has a higher self ignition point then diesel, you have to get the diesel burning first, then it burns the propane. Once the propane is burning it helps to burn more completely the rest of the diesel mix. Also since propane has oxygen already mixed in with it, its adds a little more air to the cylinders again increasing power. So adding more diesel via the intake wont do anything, it wont work.

 

[19jackal90]

I dont want to engineer a different engine. What injector did you use? What pump? Activation? Injecting through your filter lid assumes NA. I'm interested in pressurized applications. I've added adittional injectors on boosted gas apps and have an electronic additional injector controller laying around. I want to know why it wont work not just that it wont. All the air and fuel are compressed into the same spot so I'm assuming its timing.

jeez i only home brewed a water methanol injection setup on my NA truck with an electric fuel pump, i didnt use any type of injector jus a brass weed sprayer nozzle to adjust flow/mist, and a washer fluid box with the motor bypassed. i jus experimented with diff liquids- diesel additive made the worst noise then diesel fuel then watered down 2-stroke fuel ran better than all but half washer fluid and half water gave the best results.

what motor are you trying to do this to? how are you going to time it? where are you locating the injectors? this comes into play. along with the computer to be able to jump into an already running engine an knowing how much fuel to deliver so you dont over fuel and retard the motor which ive done jus by turning a pump a 1/2-5/8 turn on an NA idi. it smoked like hell but couldnt get enough air to give it more power. think of the air fuel ratio.

 

[franklin2]

You guys are pretty brave. I would never inject any sort of liquid down the intake of a diesel engine. There is almost NO clearance(.010 rings a bell?) between the top of the piston and the head when the piston is a TDC. I have always heard it's a big no-no to put anything liquid down the intake to try to help it start, and I would think that would apply while it's running also. Someone commented on it making bad noises when they injected something in the engine. Do you suppose that was the engine trying to hydro-lock?

 

[maddenji]

I guess I don't know what the end result is that your looking for.
These pumps will put out more fuel than you can use, if it was just more fuel that you want.
The propane makes the burn hotter, using the diesel that was injected more completely.
Water/alcohol injection cools the air charge and adds alcohol to aid combustion.
I don't think that adding unmetered fuel will make the burn more efficient.

 

[maddenji]

You guys are pretty brave. I would never inject any sort of liquid down the intake of a diesel engine. There is almost NO clearance(.010 rings a bell?) between the top of the piston and the head when the piston is a TDC. I have always heard it's a big no-no to put anything liquid down the intake to try to help it start, and I would think that would apply while it's running also. Someone commented on it making bad noises when they injected something in the engine. Do you suppose that was the engine trying to hydro-lock?

If the water/alcohol is added at the right rate, it immediately flashes to steam, lowering the heat contained in the compressed air from the turbo.
Remember that steam is not water vapor. Water vapor is droplets of water. Pure steam is a gas and is compressable.
Jim

 

[Agnem]

Some have said it acts as a catalyst for the diesel fuel, however I have found no proof of this.

What kind of proof do you want? Do a search on propane fumigation (as it is often referered to) and you will find numerous university studies, studies by the department of defense, and independent research activities all of which concluded that... yes, it works. The proof that does it for me, is that it reduces black smoke, which means that the fuel is burned more completely. Now if you want to argue over the chemistry aspects of it, have at it. I'm not hear to debate how it does it, but rather to restate that somehow it does do it, and putting a gas in your intake is a lot safer than a liquid. Those who run propane will tell you that it will not detenate before the diesel fuel, but that if done right it will burn WITH it. So your timing is maintained. If you add too much propane, then yes you can start to get into a situation where your timing can become too advanced, but the actual cause there of I am not sure of.

 

[dansvan]

I ran a propane injection system on my old truck. Probably will on my new one as well. Don't argue that it doesn't work, I know it does. That's what has led my to this question.

Why? So you can run a lean tune for day to day driving and when you want to get on it you can add the additional fuel with the flip of an activation switch.

You guys that are questioning injecting a liquid, I'm talking about a finely atomized mist from an injector. Not dumping raw fuel in the intake. A single injector, spraying constantly while the engine is in high boost is what I was curious about. I'm starting to suspect that the timing aspect of it is the key to it not working. I was picturing the additional fuel injected laying dormant until the fuel injected by the original injectors ignited and then that fire igniting the additional fuel allready there.