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Phil Hendrix

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Posted on Thursday, December 16, 2004 - 11:45 am:   

Hello, I am new to this board. Did not know it existed until short time ago. I would like to gain some info/advice on repowering my 1987 Eagle 15. For those of you who have already read this elsewhere and offered responses, thank you and forgive the repetition.
My situation is the coach is stripped to the frame and has been stretched to 45'and the roof raised 8". The 6V92/HT740 have been removed and now I am trying to educate myself with all of the options to repower. All I know about the existing engine/trans is that they ran 3 1/2 years ago before the bus was cut in half. While the bus sat idle due to some problems, someone stole the radiator and other misc. parts from the engine. It seems most people are inclined to suggest I not repower w/ a 2-stroke but use a 4-stroke instead. Then the issue seems to be "which" 4-stroke to use. And if I understand all that I have been reading, then the issue is what to do with the transmission and/or the rear-end so as to deal with the slower RPMs.
I have valued and enjoyed all of the imput thus far, and look foward to all the future comments. There seems to be several factors involved, short and long term vision, time, abilities, and most of all, money.
If you were in my position, what(and why) would you do?
Would you use DD, Cummins,Cat? Would you reuse 6V92? 8V92? Would you reuse HT740 and change the 3:73 rearend? Would you wait and save for the World trans when they come down in price?
Any and all feedback would be greatly appreciated by myself (and I'm sure others also). From what I have gathered, there are others doing this now or will be soon.
Thanks in advance, Phil H
Marc Bourget

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Posted on Thursday, December 16, 2004 - 1:28 pm:   

Phil,

Pretty much everything expressed on the BC site will be repeated here.

Now that you've had some time to digest that information, would you like to focus from general to specific?

Switching to a 4 stroke, in a best case scenario/ 10K miles a year, might save you as much as $1100/year in fuel costs. It'll take a lot of work and $16K (w/tranny - not including the radiator) would be a bargain.

OTOH, the number and distribution of people competent in DD 2 strokes is dropping and with the drop in ## will come less enertia against smog controls which may expand to RV's ("just because the gov't can") Geoff Smith detailed a $12K expense for this item and it's high maintenece and a performance sapper.

Then, there's the choice between the World/4060 and the Auto/Ultra Shift.

More definitive a request will get you more definitive answers.

Onward and Upward
John Rigbyj

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Posted on Thursday, December 16, 2004 - 8:52 pm:   

Repower with 8v92T/HT745( 5 speed ) also add the new large twin Radiators.
Lots of power lots of tranny at Good prices.
John
Gary Carter

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Posted on Thursday, December 16, 2004 - 9:51 pm:   

If you did the stretch totally between the axles then you left yourself a little on the short side for putting in a long 6 cylinder. On the other hand if you streched it by adding part of the strecth behind the main axle then life will be easier if you decide to go with a inline 6 banger.

If you go 4 stroke then you will need to change the rearend. Actually even an 8V92 should have a 3.33 and a 4 stroker even lower.
rdub

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Posted on Friday, December 17, 2004 - 7:11 am:   

Go to bernhardbus.com They do 4 stroke conversions on MCI, Eagle, GM ...whatever. I talked to an MC9/M11 Cummins customer. He told of starting his former worst hillclimb at 55 and topping the hill at 75. If you're planning on a long relationship with this bus, M11 or Series 60 is the way to go. Tell 'em RW sent you. Good Luck! Rdub
Phil Hendrix

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Posted on Friday, December 17, 2004 - 8:59 am:   

If I were do do the ser.60/M11 and B500/4060, will I then still have to change the 3:73 rearend? (I saw the tag/plate on the back of the axle last weekend but didn't have my glasses to read the part #. I am going to check and make sure which rearend I do have).
I do plan on keeping this bus for yearssss to come. My wife tells me we should find a plot for us, I'm not sure if she means us=her and I or...
Rodger in WA

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Posted on Sunday, December 19, 2004 - 10:50 am:   

You might check with Dave Gregory, Southern Oregon Diesel, Roseburg, OR.
Dave repowered an Eagle with - I think - a CAT.
Marc Bourget

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Posted on Sunday, December 19, 2004 - 1:40 pm:   

That was his personal Eagle, IIRC, he's also done others. More intriguing was the M-11/Allison Auto in the MCI-5, a bus I named the "Prevost Probe"

Ah, Yes, the life of the idle rich. "I think we need something with alittle more HP to tow our snowmobiles" and a 400HP M-11 MCI-5 is the result!

Actually, it's more a combination of talent and energy being a dangerous thing - to hoity-toity Prevost owners, anyway!

Dave "Mr. Modest" Gregory is my kinda guy!

Go, Dave!

Marc Bourget
Buswarrior (Buswarrior)

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Posted on Sunday, December 19, 2004 - 8:22 pm:   

Hello Phil.

No need to change the rear end to a smaller number, if you get a newer overdrive transmission.

If you are using an older 1:1 top gear, then you have to get a lower number in the rear end ratio to get the revs down, otherwise, the gains of the 4 stroke are eaten up in the spinning, and their big power is lower in the RPM, so you may still slow on hills.

The new stuff runs 4.56 and the like with a World 500 tranny. 6th gear is a 0.64:1 overdrive, 5th is somewhere around 0.7 and 4th is 1:1.

There are driveability issues with every combination. The compromises you want to make are yours to make. Be sure you know what each variable in a given power train dream will do to how it drives!

Play with the specs, and decide how YOU want to spend your money!

happy coaching!
buswarrior

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