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Discussion Starter #1 (Edited)
I was reading this article online under MSN Money, a link with helpful ideas on how to save money. It suggested that we start thinking about fuel consumption in miles per dollar instead of mpg. Kind of a businesslike approach. (They mentioned the Toyota Prius as the car with the best mpd of 14. :happyfinger: Yeah, the car is a joke, where was the VW TDI?) Of course, this number would fluctuate daily. However, I thought that this change in thinking would favor diesel engines, even though diesel costs MORE! (At least in Ohio).

You are all aware that gasoline people say that they don't like diesel b/c it smells, the engines lack performance, the engines are expensive blah blah. They also dismiss it b/c it costs more per gallon. I drove past Shell today and saw 87 for 2.86/g and diesel for 3.27/g. Maybe the gassers were right. However, if you compare say, a Jeep Grand Cherokee with a 5.7 Hemi (15 mpg, at best) to a JGC with the new 3.0 diesel, an engine of similar power (22 mpg, low est) the numbers tell a different story. The hemi gets 5.24 mpd while the diesel gets 6.73 mpd. :grinpimp: Let's take this out over 1 yr/15,000 miles. If prices stayed the same, the hemi would burn 1001 gallons and $2862.59 while the diesel would burn 682 gallons and $2228.82. I think the avg vehicle is kept 7 years so this would mean $4438.00 in fuel savings. This type of thinking makes ownership of a diesel much more attractive. When you consider that a diesel requires less than half as many oil changes, fewer pit stops, less trips in for tune ups, has greater longevity and better resale, why would we consider any other option? Let's face it, diesel is the wave of the future, gasoline should be reserved for weed wackers and starting brush fires!
 

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I was reading this article online under MSN Money, a link with helpful ideas on how to save money. It suggested that we start thinking about fuel consumption in miles per dollar instead of mpg. Kind of a businesslike approach. (They mentioned the Toyota Prius as the car with the best mpd of 14. :happyfinger: Yeah, the car is a joke, where was the VW TDI?) Of course, this number would fluctuate daily. However, I thought that this change in thinking would favor diesel engines, even though diesel costs MORE! (At least in Ohio).

You are all aware that gasoline people say that they don't like diesel b/c it smells, the engines lack performance, the engines are expensive blah blah.
I agree with you wholeheartedly, my brother believes that gasoline will be a better performer than diesel despite the fact that most of the major auto manufactures have (in other countries) introduced diesel race vehicle. It is that thinking and the congress (with their pockets lined by big oil) that will keep people away from the truth and from seeing the "light". Also, too many people believe what they are told without actually researching or at least looking into it a little.

And I live in upper Ohio along the Michigan border, Diesel is $3.25 while gas is $2.78.

Pantherman
 

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I was reading this article online under MSN Money, a link with helpful ideas on how to save money. It suggested that we start thinking about fuel consumption in miles per dollar instead of mpg.
The spreadsheet that I built to track the mileage for my truck has a "Fuel costs/mile" column so that I can see just how much it costs me in fuel per mile. Typical costs in the summer ran 14-18 cents per mile, depending on whether or not I was towing something; winter costs have been 18-24 cents/mile. :eek:

The reason I added that column was to see just how big a difference it will make once I finish my water/meth injection, and any other future changes.

And my wife said I was just being anal.......... :grinpimp:
 

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It is impossible to get the average American to consider diesel as an option. For whatever reason, the early '80s diesel are still fresh in the minds of the diesel haters.

My Sprinter van was my first diesel. I love it. I don't know my MPD but I pull a 25mpg average. I can't wait to get my Kaiser running with the 4bt. I'll go from 4 mpg with my 406 small block to....whatever I get with the 4bt has to be better.

Strange...almost every new car that we import is available in diesel elsewhere.
 

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Discussion Starter #7
I think that one of the popular misconceptions is that diesel is for big rigs, bulldozers and blue collar guys with pickups. Not the type of engine one would want in their town car or minivan. The truth is that these engines could be adapted to just about any application except maybe a motorcycle. I read somewhere that Detroit thinks so, too. They have designs on a Cadillac, half ton pickups, maybe even a (gasp) Saturn! As long as they don't ruin the affordability of the diesel engine by selling to yuppies the way they ruined the pickup truck by making it more luxury instead of as a work vehicle, as it was intended. :(
 

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I own a nissan maxima and my 4bt durango. I have the option of driving either to/from work, I use DPM (dollar/mile) as the main contributor to which i drive. What i feel like driving plays a factor too :D

I used DPM because working for the goverment and doing travel in a personal vehicle you get paid for mileage using DPM so that's where that came from, it just makes sense to me.
 

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Uh, about the bikes..

http://www.dieselbike.net/

Personally, and maybe it's a sign of deep mental issues, one of the first 5 things I thought of to do with a 4BT was to make my own interpretation of the original Roadog:

http://www.factoryfat.com/roadog.html
Haha! I read about those in a bike mag once. I hope you were contemplating streamlining the aerodynamics first!

If you think about it though, you could build quite the springer with a 4bt. Put a 8" rise on a softail frame and a 10" stretch and you might be able to shoehorn it in! It's already able to be air-cooled!! haha
 

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I've done these sums on the vehicles I own. Of course I'm in a completely different country with different fuel pricing and different fuel tax levels.

But.
The 1.8L econobox shopping trolley works out 12 cents per km.
The 3.9L diesel 4wd which pushes twice the air works out 13.5 cents per km.

A VW TDI or similar is the planned replacement for the petrol shopping trolley, at current fuel and road tax rates it'd be 9.7 cents per km.
The reason it's not lower is here diesels pay road tax per km based on vehicle weight. Up to 3 ton all those brackets are taxed the same.
 

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The spreadsheet that I built to track the mileage for my truck has a "Fuel costs/mile" column so that I can see just how much it costs me in fuel per mile.
IHRAcer, I'd be interested in a spreadsheet like that if it was something you wouldn't mind sending me. I'm just not that good with spreadsheets... :confused:
 

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I just got rid of a 1999 Tdi that I had bought for $6300 on its way to the auction. I put a timing belt and water pump, etc. in it and drove it almost 30k miles and SOLD it for $8000! Now DD is a F350 PSD dually til I get my 'Cruiser converted. Diesel is the future fuel for America, not this ethanol fairy dust our Govt. is shoving down our throats!
 

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I just got rid of a 1999 Tdi that I had bought for $6300 on its way to the auction. I put a timing belt and water pump, etc. in it and drove it almost 30k miles and SOLD it for $8000! Now DD is a F350 PSD dually til I get my 'Cruiser converted. Diesel is the future fuel for America, not this ethanol fairy dust our Govt. is shoving down our throats!
Ethanol isn't fairy dust, you got enough brains to make beer, you got enough brains to make your own gasoline alternative (Like Biodiesel is to DIesel). I personally choose Biodiesel because it's easier (and I'm lazy :tongue: ) And it within my city's rules and regulations. Sure I could make Ethanol in the city too, but it's more closely controlled and you need a few permits.


Used ethanol in my 99 Jeep Cherokee till I trader 'er in for another vehicle a year ago, she ran fine, better off the ethanol once I adjusted timing for that fuel's use exclusively.

Pantherman
 

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did some calculations yesterday, I have about 3k on my nv4500 swap:

Overall avg MPG: 23.5
Overall avg MPD: about 7.12 (assuming avg price of diesel 3.30/gal)
Overall avg DPM: about .14

for my maxima

Overall avg MPG: 22.5 mpg (really took a dump lately)
Overall avg MPD: about 7.84 (assuming avg price of gas 2.87/gal)
Overall avg DPM: about .128

It's still cheaper to drive my maxima, but not much cheaper. I need to figure out why my mileage has gone down i was getting 25-26 average. This is all mixed driving, with city driving, a little rush hour driving, highway travel, and my back and forth to work at 55-65mph travel. I haven't really done any long trips to see exactly what my durango gets on the highway, i haven't towed much either, yet.
 

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also look at fueleconomy.gov the TDI is not listed in 08,07 and the earlier years listed have low numbers. My mom has a 2002 Jetta Wagon 5sp its window tag says 50mpg highway, but the web says 45mpg a little suspect....gassers are constantly up played compared to the diesels...Ethanol is a scam somehow you get more power out of it even though it has a lower energy density how does that work :confused:
 

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also look at fueleconomy.gov the TDI is not listed in 08,07 and the earlier years listed have low numbers. My mom has a 2002 Jetta Wagon 5sp its window tag says 50mpg highway, but the web says 45mpg a little suspect....gassers are constantly up played compared to the diesels...Ethanol is a scam somehow you get more power out of it even though it has a lower energy density how does that work :confused:
I heard a rumour that the EPA mileage for diesels are taxed another 10% or so to account for the extra carbon in a tank of diesel.
Might be just a rumour though.
 

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IHRAcer, I'd be interested in a spreadsheet like that if it was something you wouldn't mind sending me. I'm just not that good with spreadsheets... :confused:
Absolutely! I modified my current sheet to reflect the topic of this thread; the spreadsheet will now show you current and overall average fuel mileage, miles per dollar, and fuel cost per mile. I left my last two fill-ups in the first two rows just for example, all you will have to do is enter your information right over mine. Here is the link, just click on it and then click the Save button to save it your computer:

Mileage Spreadsheet.xls

I have it set so that you can add or change information in columns A through E, and you can change the header where it says 'Mileage Worksheet' if you want. If you have any questions, let me know!
 

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The thing with ethanol is the octane rating. The higher the octane rating the higher the compression you can run. You get a 4% increase in overall power for each point you raise the C.R. I believe ethanol runs best around 11:1 to 12:1. Now if the test was scewed to the ethanol side it would come out about the same as gasoline. E85 has an octane rating of about 110. The main problem is that in order to run ethanol efficiently the engine has to be modified to run on ethanol by bumping up the compression ratio. Once that is done it relly won't be able to run on pump gas without dentonating so bad it destroys the engine.

On the motorcycle thing, there is currently a diesel motorcycle in Europe. I can't remember all the details, but I think it ws built in Holland. I think it was a N/A diesel with direct injection. A motorcycle engine and transmission are a relatively simple machine. Think along the lines of converting a XR 600. Find a way to add a injection pump and a small turbo. Think 100 miles a gallon?

A good machinist should be able to scratch build a diesel engine for a motorcycle if he had parts to go off of. Make the case out of high strentgh steel or 7075 aluminum. Build or have built a forged crank, rod and piston. Maybe run the injection pump of off the crank gear for the timing. Modify the spark plug hole to accept an injector. Find a small turbo for the engine and mount it. And hope the whole thing don't blow up when your running down the road. Would take a little bit, but I bet it would sell quickly. Imagine bing the first guy on your block to have a diesel motorcycle. I need to do some more thinking on this one.
 

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...Ethanol is a scam somehow you get more power out of it even though it has a lower energy density how does that work :confused:
It's simple though it does involve a few factors. I'll use methanol as an example to illustrate because I'm somewhat familiar with the numbers.

Methanol only has a bit more than half the energy per pound as gasoline. So why is using methanol a step up from gasoline in racing?

Max power for gasoline is at a stoichiometric ratio of 12.5-13:1.

Max power for methanol is at stoich of 5-6:1.

With gasoline at 18.5 KBTU and methanol at 9.5 KBTU, one can do the math and see that more energy is available from methanol than gasoline when used as fuel in an internal combustion engine.

Richest gasoline to leanest methanol results in a 2:1 ratio methanol to gasoline. This results in 19 KBTU for methanol vs 18.5 KBTU for gasoline. Consider a more "fair" scenario and compare middle stoich to middle stoich(again for power not economy) and we get a 2.3:1 ratio resulting in 21.9 vs 18.5 KBTU, methanol to gasoline respectively.

More gains are made when the engine is tailored to use this fuel. Higher cylinder pressures before autoignition with alcohol means a more efficient conversion of that potential energy into mechanical energy can be achieved.

Note that I am just illustrating how comparing energy density of various fuels does not tell the entire "story".

Ken
 
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