Running Propane
- Thread starter Gambler
- Start date
DirtyMaxx03
New member
What was your application? I would like to try to use it to get a better fuel mileage. I already have the set up, just haven't hooked it up yet. Other than buying some propane/cng, I don't really have much money involved. It will be going on a 97 12v, my signature truck. Not trying to use it as a power adder. It is my understanding that the #2 fuel mixture should be a little rich vs. lean because the propane/cng will help burn excessive fuel.
JWhite
Trained monkey
LP and CNG are fuel, if anything it will smoke MORE. If you want a quality CNG kit look up Marc Deluca. But be warned, CNG kits are pricey compared to what you can get a LP setup for (mostly the cost of the tank is higher).
Neither fuel is any more dangerous than diesel fuel, just don't be stupid. Depending on how close a CNG station is to you, LP is a better bet, BUT you won't be able to get LP filled on a truck for as cheap as your house.
Both of these fuels are good candidates for extra MPG and HP, just don't bolt on a kit and expect 150hp, typically 75 on a CNG equipped truck. The main limiting factor will be the line size/regulator flow capabilities. If it were my truck, CNG would be on it for extra mpg, already makes plenty on #2
Leiffi
New member
Since The Big Bang. They use oxygen, less left for diesel to burn clean.
90dodge
Always Broke
My guess is because they don't know what their talking about. Simple chemistry tells you unburnt fuel makes smoke.
The one thing i definetly don't agree with is that they are any less dangerous than diesel. Strike a match next to some open diesel, then do the same next to a propane tank with an open valve and tell me how it goes.
Sure, you might get better diesel fuel mileage running pro/cng, but go ahead and try it and let us know how much more your spending on the alternative fuel you are paying for. We can always use some more carnage pictures if you decide to get wild with it too. Lol
The one thing i definetly don't agree with is that they are any less dangerous than diesel. Strike a match next to some open diesel, then do the same next to a propane tank with an open valve and tell me how it goes.
Sure, you might get better diesel fuel mileage running pro/cng, but go ahead and try it and let us know how much more your spending on the alternative fuel you are paying for. We can always use some more carnage pictures if you decide to get wild with it too. Lol
JWhite
Trained monkey
I will come up front and say I was probably wrong about LP being "safer" but CNG is for sure. You can open a CNG tank valve next to a torch and it won't light. CNG has a very narrow window of AFR that it will burn.
Back to the smoke.... A CNG kit is going to inject into the compressor inlet, so let's say 1/8 (I really don't know, just putting a number up) of the air your turbo compresses is CNG, less air for diesel to burn. A friend of mine put a cng kit on a LBZ Chevy and I had to take almost 30% of the pw out to clear up smoke 100% (started with a stock tune). He is getting 38-42mpg hwy on diesel, not sure on cng but at $1.69 there is a benefit.
Back to the smoke.... A CNG kit is going to inject into the compressor inlet, so let's say 1/8 (I really don't know, just putting a number up) of the air your turbo compresses is CNG, less air for diesel to burn. A friend of mine put a cng kit on a LBZ Chevy and I had to take almost 30% of the pw out to clear up smoke 100% (started with a stock tune). He is getting 38-42mpg hwy on diesel, not sure on cng but at $1.69 there is a benefit.
Smokie Okie
New member
You will still be controlling your AFR with your foot/AFC on a 12 valve. Don't install the kit for power gain. By the time you're making enough extra power from LP you'll be detonating and blow your head gasket.
As far as installing it for fuel economy, you're simply trading one fuel for another and will still require the same amount of BTU's to get you where you want to go at whatever speed makes you happy. The BTU's from LP or CNG will cost less, but you have to figure out how long it will take to offset the cost of the kit and the headache of keeping two fuel tanks filled.
This^^^^
I ran LP for a couple of years. It didn't smoke more. Again, you're controlling the AFR with your foot/AFC on a twelve valve.
If you get an LP tank at your house you can install a wet line on it and fill your vehicle at home for the same price.
I'm not sure I follow you on your first statement. If you open a CNG valve to air and provide fire, it will burn. The tank will not explode because the fire can't follow the fuel thru the valve where there is no air, but the fuel outside the tank will burn provided that there is enough fuel.
JWhite
Trained monkey
I'm sure if you opened a tank on a house fire it might light up, but it will just blow out a campfire. Have you tried it? Didn't think so. And how many people have wet lines on a house tank? Probably 1 guy that works for a gas company.
And the AFC thing doesn't make sense, its a boost reference. And if injecting an alternative fuel in the turbo inlet, some of that "boost" isn't really air.
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Joesixpack
Pull'n it.
Duel fuel systems perform best under moderate to high load and can often equal or better diesel alone.
However under light load emissions of both carbon monoxide and hydrocarbon increase as diesels are unthrottled. The mixture becomes to lean and combustion degrades leaving partial reacted hydrocarbons in the exhaust.
The high emissions and poor efficiency under these conditions leads to the need to smart controls to optimize the conditions of dual fuel operation.
As a "performance" angle. Forget it. From a cost per mile angle its entirely possible to be cheaper depending on your cost for the dual fuel and how smart your controls are.