Somebody's got to figure out how he does it! Maybe he doesn't count the second fuel tank? Ebay item 300652160730
Its easy math, 5 city, 7 highway.
With the standard setting of 250 to 270 hp on a 8v71 and a 5 speed manual with 3:36 rear gears the ones I have been around he is not that far off driving at 60 mph friends we travel with they have a 9 with that setup he is always at 10+he never goes over 60 mph he has a throttle delay and is set at 2100 rpm no load
I was thinking it may not be far off either. I have been told the 4106 can get 9-10 with the spicer 4 speed. With my V730 at 70 MPH I am getting 7 MPG (or I think I am).
I can get consistent 11 mpg if I stay on level ground, cruise at 50 - 55mph, no wind.
But, I have a little 6V71 and 35' coach. I doubt and extra tag, 5000+ lbs extra, and 2 more cylinders can do that.
Something must be wrong if you folks are only getting 10-12 mpg, everyone I chat with at the fuel island running the 8V-71, 6V-71 or 8V-92 all seem to say they are getting closer to 14-16 mpg, so I would have a real close look at all the setting on my engine if I were getting the 10-12 mpg, something has to be wrong. ;D
Quote from: wg4t50 on January 18, 2012, 06:01:35 PM
everyone I chat with at the fuel island running the 8V-71, 6V-71 or 8V-92 all seem to say they are getting closer to 14-16 mpg,
That's only when tested using EPA's newest tri-cycle standard - 4 mpg city, 5 mpg suburb, and 7 mpg interstate ;)
Quote from: luvrbus on January 18, 2012, 03:57:16 PM
With the standard setting of 250 to 270 hp on a 8v71 and a 5 speed manual with 3:36 rear gears the ones I have been around he is not that far off.
Okay, the early MC5 or MC1 or some one of the early MCI's had a 5 speed with the dropbox... Are the 5 speeds all overdrive in 5th? Does anyone know if an early 5 speed could be crammed into an MC5B???
my brothers 4106 got 10 - 12 on freeway..8v71 and manual.. mine with auto got 7.5... 8 maybe if not going fast and on level ground.... however i never drive slow, so that didn't happen often.
I say prove it. All these vintage 40' buses that get these numbers have owners that have fairy dust in their tank or on their brains.
All crap unless you can prove it. We have made fun of these boasters for a long time on this board.
Same ones who bragged in HS how big their ..........
Well ,I was gonna stay out of this one,AS I HAVE NO DOG IN THIS HUNT, however this coach lives about three miles from me on a very posh estate i have seen it from the road, now that its for sale maybe i can talk to the owner and see what he bases his figures on ..... plus get to check out this mci!
How can anyone prove it? I know for a fact that the knut behind the wheel has a far greater effect than just about anything, because I have proven to have beat others behind the wheel in the same vehicle over thousands of miles. On one long trip in particular I was able to average 33+ MPG, while my brother was barely able to achieve 25 MPG. I also know for a fact I can beat a cruise control, because the CC doesn't have a brain. Its not able to see the grade coming and add power to pick up speed to build momentum. Its not able to see the downslope coming and let her roll so you gain even better economy as well as momentum for the next grade. CC is just an simple machine, programmed to maintain speed to X MPH within X MPH regardless of grades. Some would argue its doesnt make a hill of beans of difference. Yet most of those arguing are the ones who cant achieve higher mileages.
I will say right off, I dont have the knowledge of what any Bus is capable of as far as MPG to say what any one in particular can or could achieve. But in more than 40 years of paying attention, the numbers that keep getting reported for various models always seem to average about the same.
The question to honestly ask is, could a lead foot driver pull a Bus capable of 12+ MPG down to 5 or 6 MPG. One the same token, could a light foot pull a Bus that typically achieved 6-8 MPG up to 10 MPG? I would guess the answer on both accounts is yes.
Way back when I worked in the charter industry, I averaged 80K per year in GMCs, Prevosts, Eagles and MCIs. All coaches except the GMCs and one Prevost were HT754 automatics, some 8V71s, some 8V71Ts, some 6V92TACs and a couple 8V92TACs This was also during the nightmare 55-mph national speed limit, but we ran 60 - 65 anyway. We also had to climb 6% grades to go anywhere if the destination was more than 75 - 80 miles away. So lots of hill-climbing in the mix, not to mention idling in the summer w/ the AC on.
At the company I spent the vast majority of my time, we were required to fuel the bus when we got back into the yard after our run. So I've pumped many a gallon into a coach, and know all about foaming diesel spitting back onto my uniform! Mgt wanted the tanks full, so we all got real good a being patient getting the level up to the bottom of the filler neck.
That being said, the average results:
3-axle 40' averaged 5.5 - 6.5 mpg
2-axle 40' averaged 6.5 - 7.5 mpg
2-axle 35' averaged 7.5 - 9 mpg
These are real-world charter bus numbers, not RV conversions. Sometimes these runs would be fully loaded, including the baggage bins, on multiple-day charters climbing all over the Sierras, others could be full of fourth graders on a school field trip to the state capital - no hills involved at all. Each run was different.
So I chuckle when I see folk talking about getting 10 mpg in a 3-axle coach with a powertrain most commonly found among us busnuts. It just ain't gonna happen - BTDTHTS!!
Maybe BK can pop in here and share with us what his 417 Setras are averaging - that would be a good, modern, real-world comparison to my days behind the wheel.
FWIW & HTH. . .
;)
All diesel engines are design to burn x number of pounds of fuel per hour and over their life span what you do with is strictly in the right foot,gearing,weight and terrain some people are better with fuel management than others me I was lousy at it but could squeeze decent fuel mileage from our bus.
The Fuel Squeezer 2 strokes with a FS 740 Allison was not that bad on fuel but it is what is some people just do better depending on their setup and driving habits
good luck
At one time Greyhounds corporate fuel numbers were available online. There is a reliable source. If purple buses got 1/10 of a gallon more MPG, all Greyhound buses would be painted purple! Of course with the EPA and such Greyhound could not use fairy dust ;D
I suspect that MCI's that are full of hot air can get over 10! JIm 0311
I have some hound records from Dallas that show the 5A and 5B getting 9.4 mpg some 8's doing the same tons of 4106 GM in 10 mpg range all 240 hp` fwiw
Let's take a look at the proportions of change in this post.
5 mpg to 10 mpg to 15mpgis a DOUBLING and a TRIPLING or a HALVING or a THIRDING, depending on your current position.
What can you do with the daily driver to double/triple/halve/third your fuel economy?
You can ruin it pretty easily, but can you raise it? The laws of physics can only be stretched so far.
Are we making assumptions about the current set-up that there is something wrong?
Did not the original purpose of the coach have cost of operation as a consideration?
Google the heavy trade press. It is popularly accepted that the driver, best to worst, can fool with fuel consumption by 30%. That is where the encouragement for driver training in fuel economy and being sure the drivers know about fuel, as per RJ's post, where the drivers actually fueled the coach and had the opportunity for that feedback and comparisons.
If you make too much energy consumption available to the driver, it will get used.
If you limit the energy consumption available to the driver, it can't get used.
Witness the detail in the post by luvrbus:
240HP settings.
Cheapest parts change on your 2 stroke Detroit equipped coach?
Put the smallest injectors into it that you can find and see what you get?
As for the data collection methods...
The precision of the measuring is a huge variable.
The method and calibration of the distance measurement.
How far out does the odometer need to be off to damage the calculation?
The methods employed to fill the tank and over the calculation period, ensure that the tank is at the same level beginning and ending? You aren't trusting that every pump is accurately measuring the fuel are you?
How much fuel is in a 1/2 inch in your tank? How much fuel can be held in each degree of lean of the coach at the fuel island? Using inches, volume in US gallons is (length x width x height) divided by 231.
happy coaching!
buswarrior
Last time I was in Texas it seemed to me to be mostly flat... Not all, but mostly. I can see 9 or 10 mpg with a 240 hp setting in a country with no hills to speak of... My run through New Brunswick when I go to my other home has a 1,000 foot elevation change - but it does it about 10 or 15 times, on 6% grades or better, and I can't get 10 mpg in my pickup truck towing my car trailer!
Brian
To be completely fair, mileage is always going to be less climbing grades all the time no matter who the throttle jockey is. If you can pull off 9 MPG in the mountains climbing grades all day long, its gotta do better in the flats if you keep the speed down.
Speed is the single greatest fuel robber next to continuous speed changes. If your constantly giving it throttle to pick up a few mph, then coasting back down a few and throttling it up again, you will NEVER see good mileage. Bus, car, airplane, locomotive, it doesn't make any difference.
Regardless of its shape, a Bus has the aerodynamics of a barn door. Once the Bus is over 30 mph, air drag starts to become the greatest load the engine has to propel after parasitic losses. By 60 MPH the HP required to push it through the air is well over 100 HP. Its quite easy to find fuel burn charts on various Detroit diesels, which clearly show the fuel burn rate in gallons per HP per hour. Air drag also increases with the square of speed. Double the speed, you quadruple the drag HP. Whatever HP was needed to push the Bus through the air at 40 MPH, 80 MPH will require 4 times the HP. Or you could look at it as a 400% increase in power consumption. So then, to increase from 60 MPH to 80 MPH, which increases speed 25%, would require double the HP. There is no way your going to get the same fuel burn at 80 over 60, youll get 1/2 that or less.
Slow down, dont chase your speed with the throttle, use hills to your advantage whenever possible and safe, and do all the things ever told or written about maintenance regarding fuel economy. Then be precise in how you fill your tank, keep scrupulous records to track fuel economy, and lie through your teeth.
The only other thing that can be done, is to locate the sweet spot and keep it there as much as possible
Oh What fun we have reading these gossip wannabee hopeful maybe mpg numbers.
For me, the 12V-71/MCI7 W/10Sped direct & 3.73 with 11X24.5 got 5.9mpg always on flat land, who cares about running the hills, swaped over to the 8V-92@580hp 10spd OD, could get 7.5mpg, but more fun playing with traffic, fuel burn is the cheapest part of playing bus games, so why all the hot air ? WHO CARES, seems it is about like women lying about their weight.
Speaking of aero drag, I don't know why coaches in North America don't focus more on drag. Take the Neoplan Starliner for example:
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.neoplan.info%2Fimages%2Fstarliner.png&hash=973021ae43e24e6f44cfba0b394dc69ac198defd)
This thing has a drag coefficient of 0.36!!! That's better than some sedans!
Having a modern power train, I don't doubt for a second these can crack 10 mpg on the hwy, driven conservatively. Mercedes achieved over 12 mpg in a 82,000 lbs euro semi.
Last year my friend was driving his Crown ten-wheeler with a 270 HP 6-71T and ten-speed non-overdrive Roadranger back from Sacramento to SoCal, and at a steady 55 MPH it got a shade over 10 MPG, including up and over Tehachapi. That was with all the seats out, but it still weighed in the mid-20s. The only reason he was driving so slowly was because his tach wasn't trustworthy, and he didn't want to risk over-revving the engine - he's used to a big Cummins 855 in his Gillig. Interestingly, I was following him in his Dodge Hemi pickup and got only 20 MPG, but he says that's the best it's ever done! (55 MPH all the way down 99 through California's Central Valley is really tedious!)
Aerodynamics and Cd numbers are largely unknown to most drivers here. Try asking a car salesman what the Cd is for a new car (or how much CO2 it produces), and you'll probably get a blank frog-like expression. Where gasoline is $8 a gallon, or more, those factors are of major importance. Some years ago one of the old Crowns got up to 102 MPH (on a racetrack!), but their aerodynamics are less brick-like than modern buses. My bus is far less aerodynamic than them, but the old adage of 6 MPG at 70 MPH and 7 at 60 pretty much applies to it. Older Crowns can sometimes get 11 or 12 MPG, either with Detroits or Cummins, but I'm guessing they would have the overdrive ten-speeds.
I wonder how much drag is caused by the flat backs of most buses, compared to the rounded rumps of older buses like Crowns and Flxibles? Maybe that's why they slip through the air better, because they have smoother airflow at their rears?
John
When you compare it to other vehicles that are considered fuel efficient, these old buses are VERY fuel efficient. My motorcycle averages 36-42 MPG. The average weight with me and my stuff is probably 1100 lbs. The average being 39 MPG, that is 28.2 lbs per MPG. My 4106 if the loaded weight is 26000, that is 3714 lbs per MPG.
I am not sure I did that comparison right, but the most fuel efficient motorcycle on the planet can't touch that.
Quote from: RnMAdventures on January 19, 2012, 04:02:39 PM
When you compare it to other vehicles that are considered fuel efficient, these old buses are VERY fuel efficient. My motorcycle averages 36-42 MPG. The average weight with me and my stuff is probably 1100 lbs. The average being 39 MPG, that is 28.2 lbs per MPG. My 4106 if the loaded weight is 26000, that is 3714 lbs per MPG.
That's true - and it continues up the scale - trains are more efficient than buses, and ships are more efficient than trains.
I share Iceni John's curiosity about whether the streamlined rear-ends on old Flxibles and similar were aerodynamically better than today's buses. I suspect they must be, because it's certainly true that most of the aerodynamic drag on a bus is from air vortices around the square back end.
Of course having a long, tapered back-end is impractical, so it seems that most effort on buses (as with trucks) is going into shaping the roof. How much of this is science and how much is styling I don't really know.
Jeremy
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fpostfiles7.naver.net%2F20110522_38%2Fdaramjuo_1306026229925nOt2H_JPEG%2F100624040538_527971408_b.jpg%3Ftype%3Dw3&hash=72b9caaf80b6ae64ce0b5fb7d51d646439f4fbad)
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fbus-and-coach-photos.com.s3.amazonaws.com%2F2180.jpg&hash=3e622fdb589e2bc9adcb38936e07fcf702166f04)
I have a theory about hills and mountains, I'd like to know what you think. I've proven this with my Chevy Suburban and can only assume it could apply to my coach.
When I'm driving my Suburban I get an average of about 18mpg. However, when I drive the mountains, I do better. My theory is that going up the mountain I probably drop to 10, 12, maybe 14 depending on how hard the grade. However, when I go down, I'm probably getting 30 or 35 or more. Engine is not working at all. So, all things being equal.. the drive up the mountain is equal to the drive down. So, if I take an average, doing the math that puts me well over 20mpg.
I took a trip through the eastern mountains a couple years ago, with four adults, and full load of luggage and got a trip average of 22mpg. Normally I would say a Chevy Suburban doing 22mpg is impossible... but the numbers work.
Am I out to lunch? Would the same physics apply to my coach?
Dave
When pulling my camper behind my suburban, if I use cruise control, I'll be lucky to average 8 mpg.
If traffic is light & I can vary my speed from 5 over (down the hills) to 10 under (up the hills), then I have averaged over 11 mpg. But, it requires a lot of effort to maintain the optimum pace. :P
I had a '93 suburban that averaged 10 @ 55 to 65 mph, but averaged 13.5 @ 85 mph. Weirdest thing I ever saw. Everyone who drove it long enough had the same results.
I haven't driven my bus much, but the few tanks I have run thru, I got much, much closer to 10 than 5 mpg.
(I didn't get in too big a hurry with the old tires under the back. . . . ) ;D
The ole GM's don't have square corners, so that's got to make some difference.
Maybe that ebay bus has a bunch of air tabs on it . . . .
Paul, there are many ways to prove it, but it is not necessary because it simply is not true. Surly with your knowledge and experience you know that and this is an exercise of fun only. With that being said, I am willing to volunteer my vacation, and at the owners expense, take his bus on my next road trip leaving little Wheezy Bus sitting. I will cornstarch my feet, and powder my underwear with Gold Bond Medicated Baby Powder (because I don't want to get itchy down there on those long missions to rewrite the laws of physics) and head west on another cross country trip. Thus setting to rest, once and for all, these braggadocious 40' bus owner's mpg claims.
For BCM posterity long after the ebay ad is gone:
1982 MCI Bus Conversion
Buy it now: $25,000
This MCI has the following.Detroit 8v71, Five speed ,Manual transmission,2 brand new tires in front with mercury tire balancer.Tires on back 95%.New drums and brakes all around bus.Has new radiators.Two 150 gallon fuel tanks long range bus.10 to 12 miles per gallon.On top two low profile air 5 carrier air conditioners. maxx air power vents.Winegard in motion digital satellite mobile antenna for two receivers you supply your own receivers.12kw Isuzu diesel engine generator.100 gallons of fresh water,and 75 gallons of black and grey water tanks,In side of bus, flat screen tv,radio and cd player,1000 watt amplifier , Bose 161 speakers,,cb radio,hookup for satellite radio, Atwood distribution panel for house 12 volt and charger for house batteries,Alloc maple flooring,Berklinedoulble recliner leather,Custom cabnets with telescoping glides,Sensor convection and microwave oven,Whirlpool refrigerator,tile shower,bathroom has Sealand fine china toilet,Bedroom has extra sink ,A closet and storage under bed,All windows are double pain,The front one have dual window shades day and night, Back ones have mini blines,This bus is smoke free,Runs great drives great. You are bitting and buying a used vechicle there is no warranty.
A hired bus driver will have different motivation than a retired owner/ operator.
I'd imagine a hired driver wouldn't place fuel economy as their top priority when they had a schedule to keep & early arrivals = happy passangers & late arrivals = a bad day at the office.
Yes it is totally possible to get above 10 mpg on a tank, but to claim that that is what that bus averages just is not so. He probably decided that the tanks that got 6 mpg should not be averaged in for some reason.
Well :-\
I guess milage is important.
I have trouble keeping my bus at 55 to 60 miles per hour and I tend drive around 70 to 75. I get around 6.5 to 7 mph. I not sure whether 10 plus is possible but I am rather sure I would go crazy at 55 MPH.
Just me
John
Quote from: Jriddle on January 19, 2012, 07:16:25 PM
. . . I am rather sure I would go crazy at 55 MPH.
That is one trip that is not long enough for me to get up to 45 mph! :o
I'm going with Clifford's and RJ's figures, they appear to have a lot of data and experience to back up their statements. A verified 9 MPG in the mountains tells me it could do much better out in the flats "if" you kept it down to 60.
I don't see what the big deal is, we get 12 MPG with our MC-8 (8V71/Allison 740). 5.5 in town and 6.5 on the highway, that adds up to 12 MPG ;-) Jack
Guys, you can't be fussing over fuel milage when you drive a bus.
When it gets near empty, you fill it up. Doesn't matter what mpg you got.
If you can't afford it, get a VW van, or go on a bicycle tour.
JC
The typical highway coach in commercial service gets about 280 passenger miles per gallon, the average bus conversion gets 14.
The Eagle model 10 with a 330hp 6v92 and 740 most of those are 8 to 10 MPG,the MCI is a brick sorry guys
good luck
Quote from: lostagain on January 20, 2012, 07:07:16 AM
Guys, you can't be fussing over fuel milage when you drive a bus.
JC
Sure I can. In fact mileage was even more important to the fleets that ran these machines.
For example, this Bounder we been pushing around the last 7 years, we have accumulated over 50K miles. Most of that distance was foot to floor 70-75 mph plus, whatever she would do floored, and I averaged 6.5 - 7 mpg. Not bad. However, the last 10K miles or so I've backed off on the throttle, and found that as long as I keep it under 65 mph, I'm solidly in the 9+ MPG range and have made 10+ MPG if I don't go over 55. And yes, 55 is tough.
Had I driven 60-65 the entire 50K miles, I would have averaged around 9.5, and burned 5263 gallons of fuel. And at at average cost of $3 gallon, would have spent $15,789 in fuel.
At 6.5 MPG, which was more often the norm for most of our ownership, over 50K miles we would have consumed 7692 gallons of fuel, at a cost of $23,076, exceeding our purchase price of the Bounder itself. Slowing down could have saved us $7,287. As you can see, a 1 to 2 mile per gallon improvement makes a HUGE difference when your starting from less than 10 MPG.
So ask yourself, would it have paid for me to drive 5 to 10 MPH slower that whole time? If I figure a good half that mileage we spent $4 gallon, not $3, the savings are closer to $9,000. And thats about what I feel my foot to the floor attitude cost us. Do the math at $6 gallon, which could happen, and the cost differences are even more polarized. Also, at lower speed the rig rides smoother, I dont get so tired, I'm more relaxed, the engine runs cooler, as do the tires and tranny and everything else. So its more than just fuel economy that changes.
I dont know about anyone else, but thats a lot of money. Thats a trip to Alaska I would like to take. Or an engine out overhaul or some other big upgrade deal. Dont get me wrong, I like winding it up too, and still will if and when I feel like it and have money burning a hole in my pocket or a bad case of getthereitis. But don't gripe or complain if you see me tooling along in the right lane at 65 per either.
Ultimately, if a Bus conversion can get 10 MPG, and more, its much easier to sell to the naysayers and treehuggers who would like to believe we all out there guzzling it down at some more ridiculous rate. For most people looking at our huge RV dragging a car along, 5 MPG just sounds totally awful (" :P Ewwww" response). 7 MPG seems to be much easier for most people to accept (" ;D thats not bad" response). 10 MPG makes most people speechless (" :o " response). More than 10 makes a lot of people call you a liar (" ::) yeah right" response).
For a fleet, things get even more complicated. Similar to airlines, you can't always run at most economical speed, because the additional pay for the crew (due to slower trip) may offset your fuel savings.
Then you have things that you can't put a price on - image; especially if the company tailors to higher end charters. Showing up in a flashy Prevost then driving 55 mph down the interstate to save fuel would look, well, pretty bad.
Even further complicating things, many long trips that falls into the driver's HOS wouldn't be possible if speed dropped from 75 to 55. Having two drivers + accommodations would certainly cancel out any fuel savings.
When I'm in my own bus though, it's slow and steady at 55. Not that my bus can really go much faster ;D
Another issue is time. The difference between 55 and 65 mph is almost 20%. For example, a five day trip cross country at 65 will take 6 days at 55. That's fine if you have the time.
Quote from: Lin on January 20, 2012, 10:55:04 AM
Another issue is time. The difference between 55 and 65 mph is almost 20%. For example, a five day trip cross country at 55 will take 6 days at 65. That's fine if you have the time.
Is this because of time slowing down when one approaches the speed of light?
John
When I fire up the RV, its generally a vacation. I don't usually have to be anywhere on any kind of schedule when I'm vacationing. I usually drive faster though the nastier parts, and slower through the prettier parts. And its ironic that the places more likely to get a ticket are more often in the uglier places. Go figure.
Quote from: Iceni John on January 20, 2012, 12:20:08 PM
Quote from: Lin on January 20, 2012, 10:55:04 AM
Another issue is time. The difference between 55 and 65 mph is almost 20%. For example, a five day trip cross country at 55 will take 6 days at 65. That's fine if you have the time.
Is this because of time slowing down when one approaches the speed of light?
John
For the folks in the bus it slows down... but for the folks outside the bus it actually speeds up.... at 75 MPH it would take 7 days... etc
But inside the bus it would be like 5.5 days. ;)
To quote a famous politician,"Oops". However, all evidence has been erased.
I think someone here has a "spaceballs" RV... ;D
Quote from: Lin on January 20, 2012, 01:16:49 PM
To quote a famous politician,"Oops". However, all evidence has been erased.
:) lol - honestly I wasn't going to say anything... and then John chimed in.
Quote from: RnMAdventures on January 20, 2012, 12:28:24 PM
Another issue is time. For the folks in the bus it slows down... but for the folks outside the bus it actually speeds up.... at 75 MPH it would take 7 days... etc, but inside the bus it would be like 5.5 days. ;)
Fuel is like that too. Like when your parked for a while it seems to last much longer between fill ups. I swear, it seems like I havnt put any fuel in the Bus since it came home. My gallons per day average is almost zero.
Whats really crazy is the fuel economy we get with the Jeep taking it along behind. One time we filled it up at home, and still had half a tank when we got back. But when I calculated the mileage I was shocked to see it got almost 300 MPG.