| Author |
Message |
Marcus
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 26, 2006 - 12:12 pm: | |
I believe this subject is here to stay, and will continue going around and around. As I think more about this subject, more questions naturally crop up. Here's a couple:
1 - Will the Allison 740 mate up to my new engine of choice (be it a Series 60 or what ever). Some where in the back of my mind, I recall someone telling me I'll need a new adoptor ring to go between the two, and that is an expensive piece. Anyone want to comment on this.
2 - OK, everyone knows that if I do manage to match the 740 up to the new 4 stroke, that my resulting RPM's will be far greater than what's needed for fuel econemy. Therefore, rather than changing out my tranny, what are the options of changing out the differential gears? I know that too has to cost, but will the cost be less than buying one of those Allison 6 speeds ? |
niles steckbauer (Niles500)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 26, 2006 - 12:34 pm: | |
Marcus - most important is how can your 740 speak to the Electronic Controls of the newer 4 strokes? |
JimH
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 26, 2006 - 1:34 pm: | |
1.You will need a "Flex plate" to connect the torque comverter to the engine. they are expensive! as I recall abouyt $800.
2. Don't know what bus you have but I changed the rear gear to a 3:36 from a 3:73 in my eagle 01 at a cost of $4,400 using all new parts. Engine has plenty of torque for this change.
3. I know you didn't ask BUT -- you really need a 741 or a B500, both of which are an electroinc transmission to go with the 60 series. You might be better off to bite the bullet and get the B500 and save yourself the cost of gears and a different trans to go with the electronic engine.
By the way - and this has nothing to do with the above - I do have an extra B500 sitting here - complete with computor but no shifter or harness if interested!
JimH |
Craig (Ceieio)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 26, 2006 - 2:26 pm: | |
<shields> - this is not meant to be argumentative!
I have pondered Marcus', question as well. (Not that I am wanting to repower, just curious.)
Let's suppose that:
1) The DD S60 came from a manual transmission application and is therefore not expecting to talk to an electronic auto.
2) The HT740 currently in his bus does not expect to talk to an electronically controlled engine.
3) He is happy with his final drive ratio, or changes the rear gears until he is.
Which brings up the question:
"If the engine is not expecting to talk to an auto tranny and the tranny is not expecting to talk to an engine, can he just reprogram the shift points in the HT740 to match an S60 and bolt them together?
</shields> :-)
Craig - MC7 Oregon |
c-cooper
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 26, 2006 - 5:55 pm: | |
Marcus, the 740 bolts directly to the 740. If your old engine is a 92series you can use that flex plate. since the 740 is a non electronic trans. you can use an electic modulator{I thinck I paid about $150) as far as the gear ratio, as this is a non overdrive you can change the rear end ratio to something in the 2.80:1-3.10:1 range |
JR
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 26, 2006 - 8:21 pm: | |
I don't know what brand bus you have, but by the time you install a 60 series into a bus that had a DD 2 stroke, re-gearing the diff or changing transmissions will be a walk in the park. Unless you have some unusual fabrication skills, it's gonna get real expensive.
If you make the change, buy a donor vehicle with all the sensors, wiring harness, TPS, etc so that you aren't out looking for all the bits to finish the job. You may even be able to modify the intercooler and radiator from your donor. A bus donor would be ideal. Of course, buying a 60 Series powered bus may be a less expensive, and more dependable way to go. Other than the smallest 60 S (about 350 HP), the HT740 is not up to the torque output of a 60...although, driven reasonably, it would work. It would work with your present gearing too...just have less potential road speed and a little less fuel economy. A 60 will use plenty fuel too if you drive it like a sports car (sports bus?).
What coach do you have?
Have you checked the Berhard Bus website? They show several 60 powered buses..on is an MC9 I believe. I'll see if I can find the web address and post.
Jim Shephard repowered an Eagle with a 60. He's posted a good bit on the conversion. It was a LOT of work.
Good Luck, JR |
JR
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 26, 2006 - 8:25 pm: | |
Check this out: http://www.bernhardbus.com/
May get some ideas!
JR |
Jim Shepherd (Rv_safetyman)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 26, 2006 - 8:45 pm: | |
Marcus, all of the information you have been given so far has been spot on and it sounds like you have an understanding of the gearing issues.
Folks have made the HT740 work with the electronic engines and the transmission will easily handle the torque of most any 4 stroke.
The biggest issue, as you noted, is the RPM issue. You want to gear for about 1500 RPM at what ever is your normal highway speed. As noted, you will need gearing of about 3.0:1 (or taller) and that is not possible with Eagles not sure about other brands. For Eagle the tallest ratio you can get is 3.36 and that really is not tall enough. If your bus has a T drive without drop box, you can probably swap rear ends and get a truck rear end that can be geared correctly.
Some folks have expressed a concern about using something like a 2.9 rear end and having good starting capability. Sonnie Gray (Catskinner) had a 2.92 rear end, HT740, and a mechanical CAT engine and he has never had a problem starting on any hill.
The best gearing solutions are the Allison World or the Eaton AutoShift (both have the overdrive that you need).
Jim Shepherd
Evergreen, CO
85 Eagle 10/Series 60/Eaton AutoShift 10 speed transmission
Bus Project details: http://www.rvsafetysystems.com/busproject.htm (updated 2/9/06) |
marcus
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 26, 2006 - 11:04 pm: | |
So, to all of you that have been down this road, it looks like if I change from the 92 Series to a 4 Stroke, I'll need:
1) A different flex plate to connect the torque converter of the HT740 to the flywheel of the 4 stroke. I'm assuming this is an off the shelf item?
2) C-Cooper, you mentioned a modulator?? I'm assuming this is something for the engine? Is this too an off the shelf item?
3) Yep Jim, My Eagle does not have the a T box. My thoughts are that the gears themselfs can be changed out easy enough. Its got to be a standard housing that holds the gears. If this isn't true, someone please speak up.
WELL, LETS DISCUSS THE BEST OPTION - So, If I so repower, and I do want to bite the bullet and go after the best gearing solution such as an Allison HT-4060, what are those things running?
Looking at an Frame mounted Series 60 (Frame mounted - includes all pumps, compressors, wiring harness, radiator, intercooler, etc) I'm already at $7,500. I haven't even considered a Allison World to go along with it. Go on and SHOCK it to me. |
Russ Barnes (Neoruss)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 26, 2006 - 11:20 pm: | |
I'm still finishing my R&R of the 8V to the Series 60, but there are a few other things that I had to do after starting with a Freightliner for the donor of the 60. Oil Pan and oil pick-up - couldn't find, had to buy = expensive. Motor mounts - my original were oil soaked and junk, the Freightliner were too stiff for a bus so had to spend about $600 for Prevost. Front cover plates for oil fill. Also loads of repair parts, mofications to bring hp from 400 to 500 (not for everybody). Upgrade from DDEC II to DDEC IV needed to operate the B500 (a DDEC III would have, but not the DDEC II from the '93 engine.
It's been fun and educational. I'd do it again, and there are only two things I'd have done different. 1) When I put a rebuilt air compressor on I would have gone for more cu in to have a better safety margin. 2) I'd have looked for a 14 liter motor rather than the 12.7 - why, because I have a very heavy bus.
Cost estimate so far = Engine $15,000 and rebuilt B500, $12,500 after selling 8V and 747 for $3500. |
Brian Elfert
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, May 27, 2006 - 7:29 am: | |
MCI is really pushing the ZF Astronic tranny as a replacement for the B500. MCI claims they can replace a B500 with a ZF Astronic for less money than replacing a B500.
MCI's price for a reman B500 is $10,250, but the core charge $9375.
Brian Elfert |
Jim Shepherd (Rv_safetyman)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, May 27, 2006 - 9:51 am: | |
Again, you are getting good information. If you have a true "T" drive, you have an 01 Eagle. The 05, 10, and 15 all have drop boxes and you are stuck with a 3.36 rear gear set (about $3K new). The non-01 gear sets are unique because of the splines on the pinion gear for the drop box gear. If you have a 01, your options are much better.
Folks have touched on some of the issues on a series 60 engine conversion. I have tried to document my conversion with some reasonable detail on my project pages. You can start at the third page:
http://www.rvsafetysystems.com/busproject3.htm
When you go through the details, you will begin to understand that this is NOT a project for the faint of heart. Having said that, it can be done in a home shop IF you have strong mechanical skills, and a wide range of good fabrication tools.
One of the biggest issues as far as I am concerned was the fabrication of all of the plumbing water, air cleaner, air to air cooler, etc. You will note on my site, that I rolled beads in all of the tubing to make sure that the connecting hoses stayed in place. Just one little detail that you should think about.
The other two big issues are the wiring harness from the dash to the engine and the shallow pan. Someone touched on is the shallow oil pan. It isnt just the pan, but a whole bunch of associated parts. I have listed all of the part numbers that you will need, on page 6 of my project pages. Also page 6 contains some information about the wiring harness connections.
Hope that helps.
Jim |
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