454 to Cummins

[GCinSC2]

Well we ain't heard from Mel lately. But just to keep the pondering going, skip the whole automatic issue, go manual. NV4500 or the 6 speed NV5600. Nothing but a backup light.

I saw a Greyhound conversion bus and as built they managed to control a rear drive manual transmission power train from the front of the bus. Stick and clutch.

[Kota]

Originally Posted by GCinSC2

Well we ain't heard from Mel lately. But just to keep the pondering going, skip the whole automatic issue, go manual. NV4500 or the 6 speed NV5600. Nothing but a backup light.

I saw a Greyhound conversion bus and as built they managed to control a rear drive manual transmission power train from the front of the bus. Stick and clutch.

I think that would be a giant step backwards. I really like the Allison MD3060. I think it takes a lot of the fatigue out of those long days.

[Punch]

Originally Posted by GCinSC2

I saw a Greyhound conversion bus and as built they managed to control a rear drive manual transmission power train from the front of the bus. Stick and clutch.

I must say I'd like to see a diagram of the linkage on that. They used to call a shift like that a remote at one time..... and that one would be remote indeed!

[GCinSC2]

Punch,

I was intrigued because of that question too. They ran shifting and mechanical clutch control all the way to the driver from the rear powertrain. The owners told tales of the built for service aspect of the entire coach, including a modular approach to engine R&R. And even being able to shuttle s new powertrain to a location in the cargo bays. No fuel gage either, a dipstick sufficed for the odd check cause they all ran prescribed routes.

Many front wheel drive manuals use two cables. One could push a stub stick left to right and the other front to back. Mabe a slotted gate on the console to put you in the neighborhood of the gear. No oil cooler needed either. Just get the final drive ratio in the cruising sweet spot.

Those older 12V manual transmission combos logged untold miles as hotshot rigs many at load overload.

Just a bunch of couch racing w/o hearing what Mel is pondering.

[wxbuoy]

Originally Posted by Punch

........

A 5.9 Cummins is a great engine, but your Cummins will only cruise comfortably at 60 (which is fine if you don't like 70, which I do) and will be verrrrry noiiiiiiisy doing it, and if you thrash your Cummins to get more mph, your mpg will start to disappoint you and you'll be switching the hearing aid OFF.

I am sure nobody will disagree with either of my comments......

I think I will take a shot at disagreeing with the cummins comments.

The cummins 5.9 6BTA does indeed fit in the classic airstreams. Mine actually came from the factory with one. 1991 350. Yes, it is a front engine model..... Only one I know of. It is hooked to an Alyson transmission (don't know the number). My mechanic called it the school bus combo because it was so popular back in the late 80's and meant to haul and make many miles. It runs comfortably at 2200 rpm's at 60 mph and 2450 at 70 mph. The only difference when I go up hill is the turbo kicks in. RPM's and speed stay solid.

Engine temps are running at 180-185. In the heat of the summer (90F+) the fan clutch will kick in at 188 to keep things cool. Never got above 190 driving 65-70 on the highways in Southern Mississippi in the heat of summer. I have wrapped my exhaust and am going to get a turbo wrap to help cut down on some of the excess heat in the dog house.

As far as MPH vs MPG. I average 12-13 mpg on the highway 65 mph @2350 rpms. But on on county highways averaging 55-60 mph at 2100-2200 rpms I have gotten 15.3 mpg. Of course at 70mph on the highway at 2450 rpms I get 11.3 depending on terrain. So your right I was a bit disappointed in the mpg drop and therefore tend to driver slower to get better MPG's.

Sound; as it came from the factory it it was loud at 70mph! In the low 80's db. Livable (barely), but when the turbo kicked in the high pitched wine would make it not so pleasant. I wore ear plugs when I drove interstate highways. When I replaced the cockpit floors I put in MLV (mass loaded vinyl) in for sound proofing. Covered all that with high quality sound proofing carpet padding and carpet. Also redid the dog house with the same. Now it runs very quiet. About the same as my Chevy 2500 did. We can have conversations at normal voice levels, listen to the radio, etc. Although I did mess up and tell the DW while she was talking about her sister how I missed the old days when we wore hearing protection when driving.

[GCinSC2]

Dave,

Hard to beat owners comments. Tops my pickup observations.

Just a suggestion if you like to monitor stuff. Consider adding a boost gauge and EGT gauge. Do you need to know these values, not really but by monitoring how much boost and what the EGT's are you'll get valuable info about engine health. My suggestion would be the Westach combo gauge. One 2" dial with opposing needles, really a nice setup.

Gary

[Kota]

I've had good luck with these guys. Boost, lift pump pressure, egt, differential boost air temp(experiment).

http://www.glowshiftdirect.com/

[wxbuoy]

Originally Posted by GCinSC2

Dave,

Hard to beat owners comments. Tops my pickup observations.

Just a suggestion if you like to monitor stuff. Consider adding a boost gauge and EGT gauge. Do you need to know these values, not really but by monitoring how much boost and what the EGT's are you'll get valuable info about engine health. My suggestion would be the Westach combo gauge. One 2" dial with opposing needles, really a nice setup.

Gary

Gary,

Thanks, I am a huge fan of the cummins. I already have boost and EGT gauges (factory installed. I like to keep an eye on things while driving especially up hill. One of the things I like about the boost gauge is it shows me when my fuel filters are getting dirty since I will start to loose a few pounds on the top end of the gauge.

[wxbuoy]

Originally Posted by Kota

I've had good luck with these guys. Boost, lift pump pressure, egt, differential boost air temp(experiment).

GlowShift Performance Gauges & Pods – Automotive Boost Gauges, Pyrometer

Thanks! I am still looking for a lift pump pressure gauge. Will check them out.

[Kota]

Originally Posted by wxbuoy

Thanks! I am still looking for a lift pump pressure gauge. Will check them out.

They have a snubber that smooths out the pulses from the pump. The transducer will fail without one.

http://www.glowshift.com/instruction...bber-Valve.pdf

Some of the diesel boys claim Glowshift sells crap but I've been satisfied. And the price is right.

Handy parameter to monitor. Avoids premature replacement of filters and avoids damage from suction feeding the HP pump.

[Punch]

Originally Posted by wxbuoy

I think I will take a shot at disagreeing with the cummins comments.

But you're not! You're confirming everything I said.

1600rpm is peak torque on that engine, and generally accepted sweet spot for cruising is 1900 to 2100 rpm. This is about 50 to 58 mph for your rig. Anything higher and you are thrashing that engine. It's a great engine, but still you are thrashing it. That is why 5.9's in motor homes do not last nearly as long as 5.9's in pickups.

Anything can be soundproofed, but outside of the cocoon you have made yourself, that thing is making a lot of noise! Ask other motorists who pass you in their 454 powered motor homes And you won't be opening the windows when you cruise along either, not unless you want to be deafened.

So you have a motorhome that has a cruising speed of 60 without being badly thrashed, and is noisy as heck. So much for disagreement!

[Kota]

Originally Posted by Punch

But you're not! You're confirming everything I said.

1600rpm is peak torque on that engine, and generally accepted sweet spot for cruising is 1900 to 2100 rpm. This is about 50 to 58 mph for your rig. Anything higher and you are thrashing that engine. It's a great engine, but still you are thrashing it. That is why 5.9's in motor homes do not last nearly as long as 5.9's in pickups.

Anything can be soundproofed, but outside of the cocoon you have made yourself, that thing is making a lot of noise! Ask other motorists who pass you in their 454 powered motor homes And you won't be opening the windows when you cruise along either, not unless you want to be deafened.

So you have a motorhome that has a cruising speed of 60 without being badly thrashed, and is noisy as heck. So much for disagreement!

Cummins recommends 2000-2400 for cruise for optimum economy and engine life. They don't advise cruising below 1800. Lugging them will tear them up. Mine pulls along very happily at 2200 at about 65 mph. It breaths and cools well.

You can also assume that the Cummins 5.9/Allison MD3060 which is a very popular combo is designed to run the speed limit at reasonable RPM. 2200 just feels right. That's 6th gear.

Mine is actually very quiet up front. Exterior noise level is quite low. I get about 12 cruising 65. A little better at 62 which it really seems to like. And lower at 75. That's more of a function of that V squared thing in the drag formula.

[Punch]

I think that all Cummins owners are pretty well agreed about noise levels of their engines. It's just everyone else who has a different opinion!

I'm certainly not expecting to get anyone on this thread to agree with me, but my experience of the 5.9 engine in motor homes is that they are short lived, just because they live a hard life, with all the wind resistance of the typical motor home, and their drivers are desperately trying to keep up with diesel pusher and gas powered rigs, and end up with disappointing mpg numbers too.

If you disagree with me, that's fine, and we'll have to follow our separate opinions. Now, a Duramax on the other hand would be a heckuva MoHo power plant

[choctawmel]

Oh my! I've been out of pocket on a bicycle (actually trike, my other RV) self-contained tour this last week.
Thanks for all this good information.

First of all about the transmission: The PO had a Allison 545 installed which self-destructed about 8,000 miles back. I now have a 4L80e transmission w/TCI programmable controller. There a thread on here somewhere covering that. All I need from the Cummins is the RPM and TPS which I'm not sure how the Cummins produces yet????

Second the noise: The 454 was/is well to noise to hear the lovely wife talk to me from her observation chair w/o screaming. I've been planning to redo the doghouse cover and put something under the floor of the drivings compartment for some time anyway.

Third the heat: I have the engine oil cooler not in the radiator and under the bumper, the transmission oil cooler not in the radiator and behind the right headlight. With the Cummins I (hope) plan to redo my air dam under the bumper to include the transmission cooler, oil cooler, air/water intercooler heat exchanger. I think a intercooler will fit in the back of the right front wheel well. With all this not in front of the radiator I hope to not have a front grill problem

From what I've measured of the Cummins in the dodge the only problems will be the a/c pump location and the turbo clearance to the floor under the wife's feet. But then she's always cold anyway:<)

I have the word out and I'm looking for a motor. If I can't get it in the motor home, maybe I'll put it in the 8N tractor..... Or better yet in the Suzuki..... Crazy!!!!

And I didn't do this 10-12 years ago because I thought I was too old!!! (I still have the note book w/part numbers, where to get, drawing and measurements)

Now I got to go get supplies for a mission trip to the Maud OK area. Hope some of the volunteers that show up know which end of a hammer is the business end or it'll be a long week!

[J. Morgan]

A diesel operated up to and including its maximum governed speed is not being thrashed, and a lugging an engine is not a factor of only RPM, a lug can be felt as a "lurching".

"Modern" Diesels are a lot more flexible than they were in the 60s and 70s.





Brevi tempore!

[choctawmel]

Originally Posted by J. Morgan

A diesel operated up to and including its maximum governed speed is not being thrashed, and a lugging an engine is not a factor of only RPM, a lug can be felt as a "lurching".

"Modern" Diesels are a lot more flexible than they were in the 60s and 70s.





Brevi tempore!

I get that 'lurch'ing feeling every time I get the wrong gear in my 2001 dodge. Hop hop hop rattle!!!

[choctawmel]

OMG! Going to Kansas next week to look at a 1996 cummins. I think it's time to go for the gusto. I'll see. Maybe it'll be gone before I get there.

[Keyair]

I put a couple of diesel swap links on the sticky in the classic motorhome section a couple of years back... Good info in them. I also noticed that wxbouy's factory 345 with 5.9 12v turbo is slung differently to others... Both seem to fit. One is slung low on the side of the block, and Dave's is high, next to the valve covers if I remember correctly. Fitting the 12v seems the best option and there are engine mount conversion kits out there for C/K trucks that should work. Its a common swap and there is plenty of people who have done it. There is a guy on EBay that sells complete 6bt's at reasonable prices.
The Duramax conversion done by the guy in FL doesn't look like it was ever finished based on his blog...

[Keyair]

Here they are:

http://www.airforums.com/forums/f311...cle-38432.html
http://www.airforums.com/forums/f311...h-26956-2.html

http://www.airforums.com/forums/f311...cle-38432.html

[Kota]

Originally Posted by Keyair

I put a couple of diesel swap links on the sticky in the classic motorhome section a couple of years back... Good info in them. I also noticed that wxbouy's factory 345 with 5.9 12v turbo is slung differently to others... Both seem to fit. One is slung low on the side of the block, and Dave's is high, next to the valve covers if I remember correctly. Fitting the 12v seems the best option and there are engine mount conversion kits out there for C/K trucks that should work. Its a common swap and there is plenty of people who have done it. There is a guy on EBay that sells complete 6bt's at reasonable prices.
The Duramax conversion done by the guy in FL doesn't look like it was ever finished based on his blog...

Thought I saw a post on the test run down to the Keys on that one.

http://www.airforums.com/forums/showpost.php?p=1171841