i read an article in diesel power last month where they took a extra cab short box that was getting 14.6 average fuel ecomnomy and added a propane kit. they claimed that economy went up to 24 mpg as well as being able to roast the tires. how much propane is neede per tank? im looking to do either 5 inch exhaust , injectors or propane. was wondering if anybody here has increased there mileage? with one of these options


thanks

 

Now you have to calculate combined fuel economy. Gallons of total fuel used over the distance travels. You should get better mileage in because the propane is supposed to improve combustion in the cylinder, assisting in a more complete burn of the diesel, but if you are using it for max horsepower giddy up and go, it may go the other way. It's like anything else, it's all what you do with it.

 

i wanna keep tabs on this.

 

nobody here can tell me that injectors or propane increased or decreased there economy?

 

If you drive your truck the same with either mod, you will gain mileage. I picked up about 1-2 mpg with the Jammer nozzles. Keep in mind that propane, just like all fuel, is going up in price. Diesel fuel around here is over $3.00/gal again. The mileage increase from injectors will only cost you the initial investment (for me it was less than the cost of a propane kit), and you never have to stop and fill the tank. My .02

 

Improvements are constantly be made in engine. Chevy dimples the pistons in the newer high performance gas engines to increase turbulence and therefore improve combustion making more power from the same fuel air mass. The common rail system in the third gen trucks runs at a higher pressure then the previous gen's and makes more power through better fuel atomization because of it. An injector with smaller ports but twice as many of those ports will give you better atomization and therefore more power through better combustion. You start a fire with kindleing, not by trying to light a 24" log at the center with a match. While a molecule of diesel isn't a full log worth of fuel, it is 4 or more times longer then a propane molecule. (Alberta has the cheapest propane at the pump and I make 4 320 000 liters of the stuff a day where I work. (Sorry no freebees for me, so none for you. ) It's the way I might go next. After a FASS, an Exhaust Brake, a 4" Exhaust and the ATS Trans Commander. (That hurt my bankbook just thinkin about it.) Again, you have to install it and test to know for sure. (I hear that propane done right really cleans up combustion and reduces soot in the engine and the exhaust.) Not everything has to be done for maximum horsepower. (Woops, did I just type that out loud? I think the internal monalogue was left on external again. No wonder the wife was mad, she asked me if I thought she had gained weight again. I thought to myself "Not on your chest baby, not on your chest.") Doough

 

For the most part installing larger injectors isn't going to improve fuel economy. Any time your engine is producing more smoke, fuel economy is going down, because smoke is unburnt fuel.

Running propane will improve diesel fuel milage because it is adding extra fuel to the mix, which reduces the amount of diesel needed.

I've used propane for the last 6 years in my '01 HO. Around here, propane is usually $1.00 to $1.25 per gallon cheaper than diesel. At that cost difference, I figure it saves a couple of bucks per tankful in operating costs when I achieve a 2 mile/gal increase in diesel milage, which is about a 35 to 50 hp increase in power, and is all I run. If it gave a 10 mile/gal increase, as the article suggests, that would be nice, but believe me, your head gasket will not like it. To be safe for the engine, the increase needs to be kept under 80 hp or so. It will also loose it effectiveness as a power increaser, as the injector size goes up. It doesn't work so well when lots of diesel is injected.

The biggest down side to propane is getting the tank filled, which is a much slower process than filling at the diesel pump. I usually get around 100 miles per gallon of propane used, and with a 9 gallon tank it's a hastle.

 

My current truck actually gets better mileage with the Mach 4s than it did with stock injectors. 20-22 mpg is fairly common when driving responsibily and keeping it below 1900rpm on the highway. I was interested in the propane for my next truck if it really increases mileage without burning loads of propane to get there. I'm planning on buying a 12 valve 3500 for towing this truck to races that are a ways off and to use as a daily driver. I'm going to try and set it up for maximum mileage since it will become the daily driver.