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What's your take? Why would you perfer one over the other? Pros and Cons of both.
Gas vs. Diesel!
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Diesel:
Has more torque
Is easily modified for more power
Is great for towing
Gets better mileage
Needs more maintainence
Will last forever
Is harder to find fuel for
Is louder
Works for me. Diesel is only 14 cents more a gallon here. If you get an extra 2 mpg, you are winning with diesel. However, the extra expense can offset that pretty quick. The good news is in a couple years, the European standards for Diesel will become mandatory in the US, and it will be much cleaner, bringing in the speedy BMW diesels, and others that we have been missing out on.
Has more torque
Is easily modified for more power
Is great for towing
Gets better mileage
Needs more maintainence
Will last forever
Is harder to find fuel for
Is louder
Works for me. Diesel is only 14 cents more a gallon here. If you get an extra 2 mpg, you are winning with diesel. However, the extra expense can offset that pretty quick. The good news is in a couple years, the European standards for Diesel will become mandatory in the US, and it will be much cleaner, bringing in the speedy BMW diesels, and others that we have been missing out on.
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I don't know the mechanics behind the efficiency, but I do remember diesel powered Jettas and Rabbits getting 30-40% better mileage.drcookie said:Why diesel is more efficient if you don't mind me asking.
The '05 Jetta TDI (Turbo Diesel) gets 38/45mpg with HP 100 and TQ 177.
The '05 Jetta GL (Base 4 cylinder gas model) gets 24/31 with HP 115 and TQ 122.
Not bad for 6% more in gas price.
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Diesels are more efficient do to the way they work. A gasoline motor relies on the detonation of the gas/air mixture in the cylinder which can be a very inefficient process.
Diesels create power by compression only, there is no spark plug, just a glow plug which creates a much more efficient "burn" if you will. I believe the lubrication of the system helps as well since the diesel fuel is less refined the gasoline which aides in lubricating the cylinders and valves.
Not 100% but I believe these factors aide in the gain in efficiency. There is also the bio diesel option as well. if you had room to have your own processing station, and you were able to get all the free used fryer greases you could use, the cost for bio diesel is .55 a gallon!! Also burns cleaner and smells like french fries on the way down the road! Oh ya, only modifications needed are changing out the fuel lines from rubber to a denser polymore fuel line, unsure exactly what kind, but not expensive at all!
Diesels create power by compression only, there is no spark plug, just a glow plug which creates a much more efficient "burn" if you will. I believe the lubrication of the system helps as well since the diesel fuel is less refined the gasoline which aides in lubricating the cylinders and valves.
Not 100% but I believe these factors aide in the gain in efficiency. There is also the bio diesel option as well. if you had room to have your own processing station, and you were able to get all the free used fryer greases you could use, the cost for bio diesel is .55 a gallon!! Also burns cleaner and smells like french fries on the way down the road! Oh ya, only modifications needed are changing out the fuel lines from rubber to a denser polymore fuel line, unsure exactly what kind, but not expensive at all!
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Your description of the diesel is a little off. You are right about no spark plug, but the glow plug is not for igniting the diesel/air mixture. It is located in the intake manifold, and is used only in cold weather, to heat the incoming air for starting only. The diesel engine runs at a much higher compression ratio than a gas engine. Today's gas engines have compression ratios in the range of 8-9 to 1. Diesels have a compression ratio of 18 to 1 and up. In the fuel injected gas engine the fuel is injected into the manifold or head before the intake valve, not into the cylinder. In the diesel the fuel is injected directly into the cylinder at the proper time. It is ignited by the very hot air in the cylinder. The air is heated when it is compressed.
Diesel engines run at a lower RPM than gas engines, and as TB said, usually have much more torque than a gas engine of the same size.
TB is also correct in his other statements about the diesel engine.
The reason bio diesel is cheap is because it is subsidized by the Federal government. The actual cost of producing bio diesel is much higher than normal diesel.
Diesel engines run at a lower RPM than gas engines, and as TB said, usually have much more torque than a gas engine of the same size.
TB is also correct in his other statements about the diesel engine.
The reason bio diesel is cheap is because it is subsidized by the Federal government. The actual cost of producing bio diesel is much higher than normal diesel.
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Sorry about the mix up of info on the diesel engine, my description was off, but my mind was in the right spot!
The bio diesel refining kit can be bought with a gov subsidized grant for around 15K from the show I watched last night on discovery. One can refine 55 gallons of used oil adding all the chemicals and what not for less the .55 cents a gallon if all the used oil is obtained for free. The unit has large vats, so space is an issue, if you had a large detached garage or lived on a farm, it would be a no brainer to own one of these things since you can heat the house with it, run your vehicles with it and all at a fraction of the price. The time taken to refine 55 gallons of this stuff was around 4 hours. The guy who was featured was running this stuff in a newer VW TDI wagon and an '82 mazda pickup and was getting around 40 miles to the gallon. I have no idea what the requirements are for owning a refinery or anything like that, but, if I had the space and a diesel Mada, I'd be one happy guy, of course it does sound too easy.
The bio diesel refining kit can be bought with a gov subsidized grant for around 15K from the show I watched last night on discovery. One can refine 55 gallons of used oil adding all the chemicals and what not for less the .55 cents a gallon if all the used oil is obtained for free. The unit has large vats, so space is an issue, if you had a large detached garage or lived on a farm, it would be a no brainer to own one of these things since you can heat the house with it, run your vehicles with it and all at a fraction of the price. The time taken to refine 55 gallons of this stuff was around 4 hours. The guy who was featured was running this stuff in a newer VW TDI wagon and an '82 mazda pickup and was getting around 40 miles to the gallon. I have no idea what the requirements are for owning a refinery or anything like that, but, if I had the space and a diesel Mada, I'd be one happy guy, of course it does sound too easy.
Diesel fuel has a higher calorific value than petrol, i.e. it produces more power per pint than petrol.
Diesel or more correctly compression ignition engines can be direct injection or indirect injection (pre chamber).
Modern (European?) style engines are common rail (very high pressure) injection which improves efficiency and smoothness compared to the tractor/bus/plant style engines available in SUV's in the states at the moment.
Ford / Audi etc 2.0L Diesels will give you an average of 45-50 mpg in normal use (in a 5 seater saloon).
Even though they produce more torque they are slower reving and don't feel as powerful as the posted power figures would suggest.
Diesel or more correctly compression ignition engines can be direct injection or indirect injection (pre chamber).
Modern (European?) style engines are common rail (very high pressure) injection which improves efficiency and smoothness compared to the tractor/bus/plant style engines available in SUV's in the states at the moment.
Ford / Audi etc 2.0L Diesels will give you an average of 45-50 mpg in normal use (in a 5 seater saloon).
Even though they produce more torque they are slower reving and don't feel as powerful as the posted power figures would suggest.
They are much heavier by design because of the battering the bottom end must withstand. Thicker, stiffer block with more webbing, bigger main bearings and caps, heavier crank. And with such high compression; beefier starter-24v, 2 batteries. I want a Cummins, even if it means taking one in a dreaded Dodge wrapper.
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Cummins V8 diesel on the way in Armada wrapper for '07. Maybe you can hang on for a year?Cillyone said:
maybe not now... but maybe if they start working on diesel like they do on fuel engines we would see a lot more diesel pumps and less disadv. with diesel engines, like being noisy, heavier, and that kind of stuff. give it another 5 years. question is.. can you wait? neither can i.
One of my best, oldest friends has a absolutely pampered 2001.5 3/4t HO CTD 6spd 4x4 ext cab Dodge w/<20k miles and wants to move up to a 1 ton this spring. He only used it for vacations (long drives), no stop&go around town. This thing can nearly pull 14k lb and has been over-maintained if anything. I simply cannot pass it up, the truck is like new for less than half the new price. He keeps spreadsheets on EVERYTHING, every drop of fuel, where it was bought, for how much, ALL maintenance records, every penny that was spent on the truck and what it was for. He has gotten a documented 16.7 mpg WITH a 2500 lb slide in truck camper OVER the Sierras and the Rockies on a 3k+ mile vacation. I am somewhat limited with the tow capacity of the Armada, and I want to use my toybox a lot more than I am now, my boys are at prime motorcycle riding age and I am not getting any younger. I can't wait. Most likely the V8 Cummins will be a very nice setup, but I know the proven I6 Cummins is for sure.92TripleBlack said:Cummins V8 diesel on the way in Armada wrapper for '07. Maybe you can hang on for a year?
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Guess that's LA. Its more like 50-50 here, and Cillyone, its 9 months, your call.andy said:
Oh yeah, forgot to mention, the wife wants a G35 (350Z maybe) now instead of the Armada. We will most likely sell the Armada, I really don't want to but I can't justify owning 2 tow vehicles. I am lost without a pickup, too much work to do at the property and the utility trailer is a drag to have to hitch-up just to get a few construction supplies that are too messy/big for the Armada/4Runner. The money I get out of the Cummins/Armada change will help offset the G35 hit. I think it will all work out, and who knows, possibly in a few years maybe Nissan Cummins V8 will be on the table, when they get up around +12k lb towing power and any major bugs worked out.92TripleBlack said:Guess that's LA. Its more like 50-50 here, and Cillyone, its 9 months, your call.
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I love my G35, but even still, given the choice, I pick driving the Armada every time. I use the G35 for work and drive it all over. Drove it 7 hours today, mostly at 85 mph. Great car. Get the stick if you can deal. Also, get the sport package. I love the wing. Looks incomplete without it and it actually is functional. No problems except brake rotors and dusty pads. Go figure. They fixed these in '05. Go figure again.Cillyone said:
If you want total performance get the 350Z. It is marginally faster. If you want lux performance, get the coupe G35. It has more mods you can do to it than the Sedan. I got the sedan because I need to fit adults in the rear. Fits five adults/teens comfortably. I also love the premium package. Good luck.
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