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Author Topic: 6V92TA vs 8V92TA  (Read 4456 times)
i12fly2medford
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« on: September 09, 2007, 02:04:51 PM »


Hello everybody,

I have been looking through the posts here for a couple of weeks now, and today I decided to join and post.

I have decided to get a bus, hopefully before Christmas, but that depends on the bus.  Cash is in hand and I'm ready to go.  My Grandfather converted an MC8 back in 1992, and he is available for my consultation.  I have my own experience as well, having gutted and remodeled my house, including all new electrical, plumbing, and a 1200 sqft addition.  Anything else I need to know, I'm hoping that's what you guys are here for.   Grin

My question right now is regarding the difference between the 6v92TA and the 8v92TA.  I understand that horsepower and torque are quite a bit higher on the 8v (I believe in the neighborhood of 100 HP more based on MCI's website), but I'm wondering what kind of practicality does that offer?  I travel primarily on the East Coast, but do take trips to the Midwest, and plan to take a trip to Oregon, and Alaska in the next few years.  Very mountainous terrain there.  Will I be looking at a significant speed / power reduction with the 6v in normal fairly flat driving?  Is there going to be an issue with the 6v not making it up certain grades, like a 4 mile 6% grade for example?

I'm interested in hearing from anyone with an MCI 102 with the 6v92TA and 8v92TA with the Allison 740.  What are your experiences with these engines?

I thank you in advance for your input...

Wade Israel

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« Reply #1 on: September 09, 2007, 02:47:16 PM »

Fly,

Do a search for "8V92 Radiators".  It is a few pages back in the posts.  Knews u can use.

Welcome to the board.  We will be looking forward to learning from you, as well.

John
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« Reply #2 on: September 09, 2007, 02:58:51 PM »

Wade,
Welcome to the board.  I'm afraid I'm not much help with the specifics re. HP, etc. on the DDs, but there is a lot of knowledge and experience here.  These guys are the best!  I'm a wannabe, hoping to find the right bus, already converted, in the very near future.  You've come to the right place for help and comarodary...comoradie...comorody...friendship.
I'm near Roanoke, about 4 hours from you.
Dennis
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« Reply #3 on: September 09, 2007, 04:35:51 PM »

Hi and welcome, I can't speak to the 8V but I do have the 6V in my eagle with the 740 allison and I have all the power I need for what we do, we travel all over the midwest and some out east, the terrain varies from flat to very hilly, haven't had any experience with real mountains like would be found out west but we can travel at highway speed without any problems at all, generally maintain 70 or so on the interstates without a whimper from the bus.  I would think that either motor would serve you well as long as it had been maintained properly in the past and you service it as needed.  The best advice I can offer is to have a qualified mechanic inspect any bus that you feel would be a good candidate for what you want, it's small money that can save big expenses.
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« Reply #4 on: September 09, 2007, 04:58:56 PM »

welcome to the group, I have a 8v92 and find that it will not pull the large western mountains in fourth but drops to third and makes about 40- 45 MPH. I live nest to the mountains in the west in eastern Oregon. and cabbage hill is about 30 miles from me. So no matter what either enging will get you over the mountain and none are going to do it at cruise in 4th gear Jerry
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« Reply #5 on: September 09, 2007, 06:38:49 PM »

I agree with Jerry ... I have a 8v92ta 475hp with a 6 speed and I have to gear down to 5th on 6% grade end up around 45 to 50 MPH up the hill in eastern BC. A  6v92ta 350hp would be down to 2nd on a 4 speed tranny 30 to 40 MPH
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Nick Badame Refrig/ACC
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« Reply #6 on: September 09, 2007, 06:45:44 PM »

Hi Wade,

Welcome!

And thanks for posting.

I hace a 102C with the 8V92 and 740. Lots of power to climb hills along with enough to tag along my 6900lb Yukon.

Feel free to contact me with any questions.

Nick-
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« Reply #7 on: September 09, 2007, 08:08:57 PM »

I agree with Jerry ... I have a 8v92ta 475hp with a 6 speed and I have to gear down to 5th on 6% grade end up around 45 to 50 MPH up the hill in eastern BC. A  6v92ta 350hp would be down to 2nd on a 4 speed tranny 30 to 40 MPH

Most 6V92s in a bus won't be set to 350 HP unless hot rodded later on or maybe if ordered as a conversion shell.

My Series 60 is only 350 HP and I'm not looking forward to some of the grades on I80 through Wyoming, Utah, and Nevada.  I do have more torque than the 6V92 so that is one redeeming thing.
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« Reply #8 on: September 09, 2007, 09:14:02 PM »

The nice thing about Diesels, as compared to gasoline engines, is that if you drive a large engine at the same speed as a small engine, you'll get very close to the same fuel mileage.  But with the large engine, you'll have the option of pressing harder on the accelerator if you want to make some time. 
The buses were originally equipped with 80 injectors that would get you 300hp and 900lb/ft torque for the 6V and 400hp and 1200lb/ft torque for the 8V.  80 injectors are a good economical size, that could be driven with your foot on the floor all day and not hurt the engine.  Most like to increase to the 90 injectors that will give you 340hp and 1050lb/ft for the 6V and 450hp and 1350lb/ft for the 8V.
My bus weighs in at 31,000lb and pulling my 3750lb car, with my 375hp and 1125lb/ft torque from my turboed 8V-71, I am quite pleased at that power output.  But personally, if I were in your shoes, I'd find a bus with the 8V-92 with the original 80 injectors-that would be a good set up.  Good Luck, TomC
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« Reply #9 on: September 10, 2007, 04:12:05 AM »

I personally would go with the 8V92. When I bought my bus I picked it up in Reno Nevada and drove I80 all across the country in March of 2005 back to Connecticut. Even though it was not converted yet and all the seats were gone we cruised over the mountains of Salt Lake city in 6th and had no problems. Mine is equiped with a six speed Spicer standard as to compaired to the 740. The 740 would have been great also but I have finally learned to do some clutchless shifting with the spicer which makes it easier once you learn to play with the rpm's.
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« Reply #10 on: September 10, 2007, 02:01:16 PM »

Stephen(scanzel),

Everybody, or nearly so, has gone on record recommending the "automatic" strongly.  I have read a couple of posts over the years by people that did convert and their feeling was that they would not have converted if they had known what a serious hit they were going to take in the mpg department.  Only a couple, now mind you.

A couple questions, if you will.  What is your top speed?  How many mpg do you get on average?  What is your max speed in first?  Is you 8V92 a mechanical or DDEC?  I assume you don't have an air to air intercooler between the turbo and intercooler.  How much boost are you getting at full throttle?  I think your data will be of some interest to many people besides myself.

Thanks,

John
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« Reply #11 on: September 10, 2007, 04:21:08 PM »

Stephen(scanzel),

Everybody, or nearly so, has gone on record recommending the "automatic" strongly.  I have read a couple of posts over the years by people that did convert and their feeling was that they would not have converted if they had known what a serious hit they were going to take in the mpg department.  Only a couple, now mind you.

hi john
when you say "serious hit" are you saying there is a big difference between the automatics and the standard transmissions??....in the m.p.g.... and how big..
what can i expect to get with either??/
im just still in the looking stage,but had my mind set for a automatic ,but if theres a big difference and all this talk about trouble going up some hills ...maybe it would be better to buy one with a standard transmission...any comments
thanks
scottie
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« Reply #12 on: September 10, 2007, 10:39:56 PM »

Wade -

All else being equal, you'll be happier with the 8V in the long run, much "fatter" power curve than the six.  Has the torque to maintain speed on minor grades (freeway overpasses, for example) that the six will slow somewhat on.  Generally will pull most grades one gear higher (3rd vs 2nd) than the six, too.  Both will provide satisfactory RV service when properly maintained and driven.  The six will return slightly better fuel economy.

Here's an example of the difference between a 6V92TA and an 8V92TA, using the 300-mile run from Fresno CA to Reno NV.  The first 180 miles or so is flat up the valley to Sacramento, then east on I-80 to Roseville.  Just east of Roseville, you start climbing the Sierras, foothills first, then increasingly steep 4, 5 and 6% grades for 70 miles until you crest Donner Summit at 7,229 ft elevation, before dropping down into Reno.  The 8V92TA-equipped coach will pull into Reno all of maybe 10 minutes ahead of the six-powered coach, and burn about  5 - 10 more gallons of fuel in the process.  BTDT, lots of times.

Another example, and this one really is more dramatic.  On the 400-mile run from Fresno CA to Las Vegas NV, the 8V92TA-equipped coach will arrive almost an hour ahead of the 6V.  The reason here is that there are lots of long shallow grades on I-15 between Barstow and Vegas.  These are just steep enough that the six will have to drop from 4th to 3rd, and stay in 3rd for miles on end at 50 mph, whereas the 8V will keep on running 65 -70 without hardly breaking a sweat.  Interestingly, on this run, the 8V gets better fuel mileage.

Doesn't matter if it's a stick or an automatic, running times are about the same.


John -

Using only STOCK MCIs as an example, both the 4-spd stick shift and the HT-740 automatic max out at about 15-20 mph in first, 30-35 mph in second, 45-50 mph in third, and around 75 in fourth.

Obviously, tire sizing, rear axle ratios, and different gearboxes will change these numbers, but this is a good, general guideline.

FYI, it's the GMC V-drive folk who take the biggest hit, fuel-economy wise, when switching from the OEM 4-spd stick to an automatic.  Due to the design of the V-730 automatic, between the different bevel gear ratio and only being a three-speed, the combination combines to drop the mileage anywhere from 2 - 3 mpg vs the stick shift.  This is not as much of an issue with T-drive coaches.


Scottie -

Fuel mileage is sort of a moot point when you're talking about a vehicle that has the aerodynamics of a BRICK!

However, based on my 25+ years of experience in the bus industry, I can tell you that most 40-foot, three-axle coaches with OEM two-stroke Detroit powertrains get between 5.5 - 6.5 mpg overall, regardless of whether its a stick shift or automatic.  Those folk who run only in the flatlands will do slightly better, those of us who have to deal with Rocky Top will get slightly less.

You will always wish you'd bought the automatic when you get stuck in rush hour traffic, find yourself on city streets with poorly timed stop signals, or trying to wiggle your way into a campsite.  For overall driving convenience, you cannot beat the automatic, even if the fuel mileage suffers somewhat (about 1 mpg city, 0.5 mpg highway).



Wade, Scottie, and other newbies/lurkers -

You must change your mindset about driving habits/styles when you get behind the wheel of a bus, because it's completely different than a car (or a stick 'n staple RV, for that matter).

Remember Aesop's fable about the Tortoise and the Hare?  This little fable becomes an excellent analogy when it comes to operating a coach.

If you expect Hare-like performance out of a bus, you're going to be severely disappointed.

OTOH, if you treat the experience like a tortoise, you'll have a GREAT time.


FWIW & HTH. . .

 Wink



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« Reply #13 on: September 10, 2007, 11:37:00 PM »

Scotie,

I think Russ covered it in his excellent post.  3 mpg is a "serious" hit.  I don't remember that it was a V drive.  My memory is that the "T" drive guys were talking about a 2 mpg reduction.  I am not contradicting Russ as he has first hand experience in many coaches over many years.  I can say that the mpg reported by different people would lead you to believe that they are driving different airplanes.  Big spread!  6 to 7 is what I hear about the 8 most of the time.  If I had one and couldn't get 7, I would be trouble-shooting.  Met a guy with a Sceinic Cruiser with an 8V71 with a three speed stick that swore a holy oath that he got right at 10 mpg and he was a trucker by profession and equally amazed.  No matter what you have, your driving technique will impact mpg performance dramatically acording to everyone.

Here again, from the professional drivers to the ther rest of us the advice is to get the automatic.  I think the ultimate bus transmission weapon is the "select shift" for a manual engine and "Auto select(?)" for an electronic engine.  10 or 13 forward gears from a Road Ranger and a slot for every occasion and 10% better mpg over a standard shifter.  You won't find that as OEM equipment...you have to do that one.

Food for thought.

Good luck,

John
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« Reply #14 on: September 11, 2007, 04:22:28 AM »

thanks guys
thats what i figured,i just wanted to hear it from the pros!!
scottie
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« Reply #15 on: September 11, 2007, 05:22:20 AM »

Wade, you have had some great responses.  I even typed one, only to have it lost in the transmittal Cry  I will try to reassemble some of my thoughts.

First of all, be very careful if the 8V92 is a conversion.  If not done correctly, it will have a pretty fair chance of having heating problems.  If OEM, you will probably like the 8V92 for reasons already mentioned.

Next consideration is mechanical vs electronic.  The board is pretty divided, but my strong opinion is that electronic is much better.  Electronic gives much better engine protection and you don't have to find someone who truly knows how to run the rack on a two stroke.

Next, see if you can stretch your budget a bit and look for a bus with a four stroke (Series 60 or Series 50).  There are RTSs with Series 50 and some MCI also had Series 50 (mostly re-powers). 

John, there are late model buses that have AutoShift (or ZF equivalent) transmissions. 

I love my Series 60 and Eaton AutoShift.  I have a gear for every need (especially important when going down a steep mountain with the Jakes on!!!).  I have averaged a bit less than 8 MPG over 30K miles.  A lot of that was driving over the big "hills" in the west Grin  On this trip I have averaged over 8.6 on a level trip through CO and NE.  This is a very accurate value based on the engine computer/Silverleaf.  My Eagle and toad weigh over 41K.

The only issue with AutoShifts are that they are slower on acceleration.  However, I get to hear the system make 3-4 shifts before I cross an intersection Grin Grin

Just some thoughts

Jim

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Jim Shepherd
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« Reply #16 on: September 11, 2007, 08:24:34 AM »

Jim,

What a testimonial Smiley  That newer busses have your setup stock is a moot point to me as they aren't even on my dream list.  Your mpg would be sufficient motive alone.  As would the option of gears for up or down the mountain safely.  Being able to start on ANY hill has got to be worth something in the dream catagory. 

I am confused about your comment that the Autoshift is slower in acceleration.  Can you expound on that?  Three shifts across an intersection sounds fast to me.

Great post from you.

Thanks,

John
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« Reply #17 on: September 11, 2007, 04:21:58 PM »

John, most folks think the slower acceleration is due to the time between each shift.  That is not a big issue.

With an automatic transmission, the engine stays "on power" and as a result, the turbo stays spooled up to a major degree.  With the AutoShift, the electronics backs the power off to break the meshing of the gears and then matches the engine and transmission speeds for the next gear.  During this 2-3 second process, the turbo has a chance to "spool down".  The loss of turbo speed and boost are magnified in my application with some pretty long runs from the turbo to charge air cooler and then to the intake manifold that must be brought back up to pressure.

To give you a feeling, my acceleration is about equal to a lightly loaded semi. 

Under most conditions, the acceleration is not an issue at all.  If I need to get the maximum acceleration, I go the the "manual" control and run the engine up against the governor for most of the shifts.  That way, the 500 rpm drop results in the engine being in the 1400-1500 rpm range at completion of the shift and the turbo reacts much quicker.  The typical Eaton software programs the engine to shift at about 1800 under full throttle.

Hope that all makes sense.

Jim 
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« Reply #18 on: September 11, 2007, 06:58:29 PM »

Unless you get really lucky, a nice 8V92/102A3 factory unit is going to be hard to find. 
Keep in mind that the mere presence of an 8V92 doesn't garuntee a large HP engine.  They range from 350 HP up to about 500 HP in a coach.   They all produce a good bit more torque than a 6V92.
An 8V92 will get as low as 3 or 4 MPG if driven up mountainsides at highway speeds...until they get hot.  Which they are know to do with disturbing frequency.  The later "C" model has vastly improved cooling systems for large engines.   
If there is any way possible, save a little more bucks and find a 4 stroke auto "C" or "D" MCI, or maybe a Prevost 4 stroke.  Prevost built more manual transmission equipped buses.  There are a few MCI D models with manual.  I'd definitely buy an automatic. 
Buses with manuals are not geared for close work, or starting on hills.  They are way too tall.  Learning to drive a manual coach may prove to be expensive, and could your spousal component drive it during an emergency?   Anyway...manual coaches are not at all common.
I've got a 6V92 in an MC9 which is similar to what you are looking for...not as wide.  Identical running gear.  Gets upwards to 7 MPG on the flats and runs up and down the interstate at 70 MPH all day. 
Does not climb the mountains...as has been discussed.  Nor will most 8V92s.  They don't exactly scream over the hills...just add one gear up and that's what a larger 2 stroke buys. 
You seem to be pretty close to me in Charlotte (NC?)...I'm just South of Matthews in Indian Trail, NC.
Are you aware that a  Bus Rally is scheduled for Oct 12/13/14?  Appox 3 hours away in Western SC....Cleveland, SC.  Palmetto Cove Campground located about a half hour on the other side of I 26.
May want to drive over and check out the homegrowns!   You'll get some good ideas...and some not-so-good ideas. Wink  I can show you quite a few not-so-good ideas!   If you have the opportunity, Bussin 2008 is also on schedule for Dec.  Arcadia is a very large bus rally.
No matter what you buy, take a good bus mechanic with you!  Look for rust, leaks, drive it enough to rule out heating problems...and just assume that the bus AC won't last long without major $$$ injection. 
Give me a call at 704 650 0235. 
Cheers, JR
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JR Lynch , Charlotte, NC
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« Reply #19 on: September 11, 2007, 07:28:30 PM »

One more point...I promise!   I saw a post that indicated that any fuel mileage below about 7 MPG would be a sign of problems...not so.  Most 6V92s driven at 70 MPH will see about 6 MPG.  Same's true for 8V92s on flats.
An 8V71 is a different animal altogether.  8V71s will get 2 or 3 MPG better than a 6V or 8V92.   An 8V71 is a much smaller engine that's usually coupled to a manual transmission...not always, but pretty common in GM coaches from where these fuel mileage comparison arise.   GM fuel mileage is one subject...MCI and Prevost 6V and 8V92s are another.   An 8V71N is an excellent motor, but naturally aspirated, it will not compete with turbo 92 series engines.  Nor will the 2 strokes compete with a 60 series. The newer the better...if one can afford the price.
An 8V71 is typically about 270 HP.    6V92TAs start at 270 HP (transit coach engines) and range to 350 HP in buses.  8V92TAs start at 350 HP and go way up from there...whatever the radiators can stand.
GM buses will get much better mileage than a  40' MCI or Prevost. 
Most Class C motorhomes get about 7 MPG too. So what the problem?  Wink
I'm totally done now. 
JR
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JR Lynch , Charlotte, NC
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« Reply #20 on: September 12, 2007, 08:06:56 AM »


An 8V71 is a different animal altogether.  8V71s will get 2 or 3 MPG better than a 6V or 8V92.   



JR -

If you're talking about the 8V71 in a GMC, you're correct.  The 40-foot Buffalos are also about 3,000 lbs lighter than the others, which accounts for a lot of that difference.  4106s are lighter still, which is one reason they were so popular with operators, due to their economical and dependable operating characteristics.  The Scenicruisers, OTOH, return mileage similar to MCIs, since they're heavier.

However, IBME that the 8V71 in an MCI, Prevost or Eagle (all three-axle, forty-foot coaches), gets virtually identical mileage as the 6V92TA, somewhere in the 5.5 - 6.5 mpg range.  BTDT, have the log books. . .

102A3 MCIs with OEM 8V92TAs are out there, probably more common west of the Mississippi due to the Rockies and the Sierras.


I believe Wade was looking at and trying to decide between a 1990 102C3 with the 8V92TA powertrain, vs an 1984 Eagle with the 6V92TA.  My recommendation still stands:  Buy the newer coach.

FWIW & HTH. . .

 Wink

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« Reply #21 on: September 12, 2007, 08:17:35 AM »

On my last trip up and back from Mammoth Lakes, Ca I averaged 5.7mpg and was satisfied with that because of my improved performance after turboing. 

Fuel mileage is completely determined by the amount of lead in your shoes.  If an automatic bus followed a manual bus and duplicated the performance, the fuel mileage difference would be very small. Most automatics get worse mileage since most drivers love to mash the pedal since it is so fun to accelerate fast.  Allison has done tests with large fleets, and once the drivers are educated to driving techniques on an automatic, many times the Allison will get better mileage than a manual transmission truck with a bad driver.  I rarely mash my motor from a stop.  With 4.56 rears and the V730, on light acceleration, the transmission will lock up in second at 1600rpm and will drop down to 1100rpm, thats at around 20mph.  So in town, I can be mostly in second lockup between 20 and 45mph.  V drives will always get worse mileage than a T drive, since the transmission has to reverse the rotation of the engine and with the V730, only 3 spds.  My bus is geared that at 2100rpm I'm doing 67mph by my GPS-which is just fine for me.  If you could be at around 1800rpm with the 2 stoke, that's the best for fuel mileage.  Good Luck, TomC
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« Reply #22 on: September 12, 2007, 03:15:35 PM »


An 8V71 is a different animal altogether.  8V71s will get 2 or 3 MPG better than a 6V or 8V92.  



JR -

If you're talking about the 8V71 in a GMC, you're correct.  The 40-foot Buffalos are also about 3,000 lbs lighter than the others, which accounts for a lot of that difference.  4106s are lighter still, which is one reason they were so popular with operators, due to their economical and dependable operating characteristics.  The Scenicruisers, OTOH, return mileage similar to MCIs, since they're heavier.

However, IBME that the 8V71 in an MCI, Prevost or Eagle (all three-axle, forty-foot coaches), gets virtually identical mileage as the 6V92TA, somewhere in the 5.5 - 6.5 mpg range.  BTDT, have the log books. . .

102A3 MCIs with OEM 8V92TAs are out there, probably more common west of the Mississippi due to the Rockies and the Sierras.


I believe Wade was looking at and trying to decide between a 1990 102C3 with the 8V92TA powertrain, vs an 1984 Eagle with the 6V92TA.  My recommendation still stands:  Buy the newer coach.

FWIW & HTH. . . Wink

Yes on the GM fuel mileage, and definitey I agree on the MCI versus the Eagle.  The MCI "C" will make a super conversion.
And, while I'm at it, I'm not at all against 8V92s....wish I had one.  But, when the are retrofitted into dual radiator MCIs, the result is often heating problems.  Expensive to fix, but fixable.  A factory 8V92 unit with the big rads would be a desirable package in my opinion. 
Best, JR
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JR Lynch , Charlotte, NC
87 MC9, 6V92TA DDEC, HT748R ATEC

"Every government interference in the economy consists of giving an unearned benefit, extorted by force, to some men at the expense of others.”

Ayn Rand
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« Reply #23 on: September 12, 2007, 06:52:03 PM »

Gentlemen How would the S50 compare to the above? With the 740 or B500?  Mike
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NJT5047
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« Reply #24 on: September 12, 2007, 07:14:59 PM »

Very desirable.  The later version of an S50 is a great powerplant.  It would be better paired with a B500, but an HT 740 would handle the engine. 
It will get better fuel mileage, has good torque, will outlast a 2 stroke, and is repairable by most current DD mechanics. 
It may not be quite as smooth at idle as a 2 stroke, but with the correct motor mounts, they are plenty smooth enough.  Anthing off idle is smooth.
An S50 would be a better choice.  I would guess that it would be found in a good bit more expensive coach...unless you find an ex-transit.  Transits don't make the best conversions unless you understand what must be altered (and willing to do the mods) to get highway speeds and accept the generally worn condition of the powerplant.  Still, an RTS properly massaged is a great looking, great driving coach.   
OTR coaches  with S50s are getting into 1993 and later, unless it's a retrofit.  Homegrown retros may not be such a deal.  A factory installed S50 would be cool. 
JR
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JR Lynch , Charlotte, NC
87 MC9, 6V92TA DDEC, HT748R ATEC

"Every government interference in the economy consists of giving an unearned benefit, extorted by force, to some men at the expense of others.”

Ayn Rand
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« Reply #25 on: September 12, 2007, 08:06:34 PM »

Regardless of the power plant, I will add to the tortoise and hare story. We recently traveled with two other families both of which have chipped Diesel pickups pulling 10,000 pound trailers. Minnesota to Grand Tetons and back again. Our Mc-5 has the 8-71 with N65 injectors 4 speed spicer and a 140 gallon fuel tank. The pickups are way faster off the line and can generally maintain higher speeds than the 70 mph we drove. All three of us started every morning at the exact same time and the 871 powered MC5 always arrived at the destination ahead of the diesel pickups at the end of the day. The pickups lose about 20 minutes every two hours for fuel stops. We didn't have to fuel up until the end of the second day. We still stop for bio breaks but they typically are much shorter in duration.
(I was suprised because I have a chipped diesel pickup that used to pull a 10,000 pound trailer!)
Fred  Cool

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Fred Thomson
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« Reply #26 on: September 13, 2007, 08:04:17 AM »

Following up on Fred's post, he pointed out a good thing about buses.  They have large fuel tanks and can go a long ways before fueling.

On a 4,000 mile trip with an F350 and large travel trailer we had to stop every 3 hours or so for fuel.  We were lucky to get out of a fuel stop in 20 minutes and it was usually 30 minutes or more.  Everybody ran inside to buy food and use the restroom. 

With the bus, I get 7 to 8 MPG and should make it 900 miles easy on a tank of fuel.  We might need to stop for smoke breaks occasionally, but we can stop at a rest area and save a ton of time.  I even figure we can travel a little slower to save on fuel and still make better time than the old F350.
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