MPG is so subjective. The point is, not everyone knows how to drive to achieve maximum fuel economy, and because they cant reach it, they often argue no one can.

This may be true, however. I saw there are contests with folks who drive super distances in somewhat regular cars. They drive 45-50 mph and no faster. They coast at every concievable opportunity regardless if it could pose a safety issue or just be annoying to the zillion of folks behind them. They use no A/C no matter how freaky deeky hot it gets. They put tape over door handles to reduce drag, and the list is virtually endless. All this would improve MPG -- HOWEVER, come on, who is going to do this and do it every second of every driving moment ? Does this really mean one is really getting 43 MPG in our beloved MB W123's ? I dont think so ... But who knows ? Correct ?

I'm sure a dedicated HYPERMILER could achieve 43mpg consistantly in one of these cars, but like I posted above... the modifications needed would make the vehicle very difficult to drive... and enjoy.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

I'm not talking about taped over door handles and driving like an idiot. I'm talking regular normal people. Two guys driving the same exact car, doing the speed limit, can get dramatic differences in fuel economy by very minor differences.

My brother and I drove my Renault R-17 out to eastern New York (east of Albany) back in around 1985. We each took turns driving about 300 miles, about 3/4 tank of gas. I kept records of gallons used and miles and started comparing. For the entire trip, my average MPG was 36 MPG. My brother never got above 29, yet we both drove the speed limit, well, basically we got behind a fast moving semi and "cruised".

We started watching each other and he figured it out before I did, it was his foot. He was constantly trying to correct his speed, so his foot was continually giving it some gas, then easing off. I on the other hand, kept a steady foot and allowed the car to speed up or slow down as the road grade or wind changed. I guess you could honestly say that I use my foot like a throttle lock.

For people like my brother, cruise control helps them do a lot better, whereas for me it always makes me get worse mileage, and Ive been beating cruise controls since I started driving my Dads '73 440 Chrysler New Yorker, and got especially good at it on a trip to California we made in 1974.

My Dad was legally blind (just under the legal limit for a DL, and so, couldnt legally drive, and my Mom didnt want to pull the trailer. So at the ripe old age of 15, and with only a drivers permit, I drove us out to California and back, almost 8,000 miles, pulling a pop up camper that weighed 1700# empty and averaged almost 18 MPG for the entire trip, and was almost always over the legal speed limit (55 national at the time). My Dad never figured out how I did it because he couldnt get more than 17 out of that car, trailer or not.

I also once drove a Renault R-5 through three tanks of fuel, and averaged nearly 60 MPG, by driving like the hypermilers, though I have never in my life blocked or impeded traffic. I pull over if people get up behind me, or pick up speed. People who intentionally block or impede traffic should be hit with phasers on kill, and sent into oblivion.

The one ive never been able to master is our Ford Expedition. Its gets 11.5 to 12, and there doesnt seem to be any way on Gods green earth to do any better.

And, I as I said, it could be true. I just know pushing 3,500 pounds with a bunch of pumps, it would be the unique experience vs. the common event. I agree that I don't measure the exact milers per gallon for every gallon. It is the average. Once I get my new MB set up, I am going to try to set up with some degree of exact / scientific way of determining what my MPG is. I too am shooting for 40 MPG, but I will have a very modified MB W123. We'll see ... maybe I will be able to post some precise info on some fuel saving antics of mine, but then burning grease, I really dont care since my out of pockets are around 10 cents per gallon.

I had some old books on diesels, that for some reason ive lost? Years ago, before the EPA stuck their nose in, diesels were "tuned" for best performance based on available fuel and climate. I always forget which way is which, but IIRC, advance IP timing for power/economy, at the expense of good cold starting, retard for better cold starting at the expense of power/economy.

I do have an old manual on the Ford/Navistar 6.9, and early on they timed them for the available Cetane.

I have also read that diesels generally are most efficient at full load, so unlike what we often see in gasoline engines, larger diesels wont gain us mileage. In fact what used to be written was looking for the sweet spot. This is a particular engine speed, RPM, where full combustion takes place just before the exhaust valve opens. If the engine spins too fast, your blowing still burning fuel out the tail pipe. If you spin too slow, combustion occurs long before the exhaust valve opens. In both cases power is being wasted. The idea is to use the available charge of fuel to produce the greatest amount of pressure to the piston, for the greatest amount of time.

So yes, slowing the engine down can have an enormous effect on fuel economy. Not necessarily slowing down per se, but matching piston speed to the speed of the burning fuel. The flame should chase the piston all the way down, burning itself out just as the exhaust valve opens.

So obviously fuel quality plays a great part as well, both in burn rate/speed of combustion (cetane), as well as energy/BMEP (BTU). I would imagine that regardless what is said or isnt said, the various states and localities are screwing with diesel additives and blends to effect emissions, and those effects will effect fuel economy as well. Thus someone in one region could get different economy than someone in another, with comparable vehicles driven equally.

The EPA doesnt care one iota about fuel economy, to them its only tail pipe numbers. And its the most idiotic way to solve the problem one could imagine. Cars getting 30-60% worse economy than they could otherwise doesnt make great sense to me. They should strive for "balance".

Actually, the real resource saver overall would be buying just one car that is built to last a life time. Obviously, wrecks and accidents would impact that but think about all the resources saved if one just needed one car during one's lifetime. That concept outguns any EPA theories on the carbon footprint issue hands down.

It really does make a difference on the mpg by the way we each drive our cars. ever pay attention how people drive from one red light to the next? It is usually hammer down right until the last moment, and then they lay on the binders. light turns green, and they launch it to the next one.

I try to look down the road as to what is coming up so Iam not cought off guard. I see the light has turned and I take my foot off the throttle and slow down and try to time it so when the light turns green, I can keep rolling and slowly pick my speed back up. while the rest of the pack is racing off to the next red light.

Of course I usually PO the guy behind me. and I get all kind of facial expressions and hand signals, and usually they race around me to beat me to the light.


The same in freeway driving in heavy stop and go traffic. I try to stay in 1st gear and idle along with 3 -4 car lengths between me and the guy in front. sure some DB will fill it in and I back off a little to compinsate. this is my buffer zone, and iam watching the rear mirror. everyone is fighting for position, and by the time we get 2 miles down the road, the guy is 2 cars in front, or 10 cars back in the other lane depending how many time he switched lanes stratigizing.


when you have to stop, and then get 3000 lbs moving again vs just keep her rolling, takes more fuel.

When I do have to stop, then get going again, I get her rolling in 1st gear then shift to 2nd, the guy behind me launches it then has to nose dive on the brakes as Iam shifting to 2nd, (to stay out of my trunk) then I hit 3rd and pull away from him as I see more hand signals etc.... usually in town we never get out of 3rd.

Last may we took a trip to Portland, Or. for the grand daughters 3rd BD. had the car loaded down to the max. (1980 240D, 4-spd with a 3:58 Diff.) I had swapped the 17gal tank for a 21. drove about 100 miles to Lathrop and topped off the tank, filled to the tip of the neck.
Drove to Wilsonville, about 5 miles from Portland for the motel. we were pushing it 65 - 70 all the way, 634 miles, and got 33.56mpg via the spedo. this was on I-5 all the way. (forgot to turn on the GPS)

The trip back home, I tried to keep the speed 55 - 60 all the way back to lathrop. 38.74 via the GPS, and 39.34 via the spedo.

The 3:58 Diff is 3% higher geared compared to the 3:69 the 240`s come with. so I believe this really helped on the increase.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

+ a MILLION, buy this man a BEER. If more people (or the flippin EPA) would consider the energy that went into making a car, man, we could change the world.

But cars that last dont make jobs. And regardless of the EPA's expressed intent, its always about jobs. And money. Cant forget money. Why you think they dump so much salt of the roads up north, it sure as heck isnt all for safety. Its to destroy the cars so your forced to buy another.

I remember a Monster Garage episode where they were building the fastest street line stripper out of an Indy car,the trannie part was to be mated to
the motor .The response given by Jesse James was,If you have a mill ,a lathe ,and the right tools everything is straight bolt up.If someone was given the task of designing a 5 or 6 spd standard to bolt up to the 617 ,what would be the trannie of choice? A 5spd has always been a big part of the golden goose for the 300d,cd and td crowd.RLEO just sold his wagon recently which he installed this setup , if the kit was available what kind of price would we be looking at? $1000.? I remember years ago someone building such a Kit ,Ill search and post up if I find it.

Youtube browsing and found this
Om617 rebuilt and a 5 speed trans - YouTube

PM OM616 he's the man for the job. 617->GM kits run around $1,000

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$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

HERES SOME ADAPTERS PLATES,4SPD ,5SPD ,and AUTOMATICS
Mercedes Diesel Engine Adapter Kits
The attempt here is to adapt the 617 to another vehicle on this site,here its a jeep.The trannie swap install to a mercedes has another list of questions to answer .To begin you would want to know how wide is the tunnel vs the swapped trannie ,the trans mount ,the shifter linkage , the driveshaft either to short or to long ,custom install etc etc etc $ $ $.If your a diy guy with a shop you could build all the parts then sell this conversion ,the plate is already being sold ,its all the other pieces to build a great 5spd conversion to make it a complete kit.If a $1000 target is kept I dont doubt this would be a seller to those wanting the 5 spd conversion without hunting for a rare 5spd MB STICK AND HAVING ALL THE PARTS NEEDED at your disposal during INSTALL.

I emailed that placed and asked about GM automatic transmission adapters and they said they planned on doing one this spring. I think a 700r4 with a 3.46 rear would be a great combination.