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Discussion Starter #1
I'm finding more of these with less mileage than the Dodge counterparts for about the same price.

Can anyone tell me if there's any major or minor differences between the two beasts? How it will effect a swap? and whether it's worth it or not?

...looking for reason to desuade me now rather then digging deeper and realizing issues too late.
 

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I used an F700 engine in my truck which is essentially the same. They have the "frieghtliner" accessory mounts so everything is a little different. Liked it because I could mount the A/C compressor under the alternator without chopping the frame. There is an idler there you can build brackets to replace. However, the fan mount is too high for a pickup, so you would have to get a dodge mount to use a factory fan. I used two electrics. I think all of those engines are P7100, so you have endless potionential on power. They are however quite lazy in factory setup. I moved the fuel plate forward, AFC housing forward, loosened the star wheel, and did the washer mod on the governor. After those mods, it is very responsive and makes all the power I need.....I still want more, but dont need it ;). It will quickly accelerate my 1 ton, crew cab to whatever speed I want to go.
 

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I am using a 5.9L cummins out of a school bus (read signature) There are a few differences: motor mounts, power steering pump, oil pan and oil pickup tube, accessory brackets, and so on.....nothing major, I guess it depends on what you plan to do, and if "Dodge style" accessories are what you want to keep....

Heres my build up thread:
http://www.4btswaps.com/forum/showthread.php?p=21569#post21569
 

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Discussion Starter #4
That's good to know. I was planning on using electric fans as well so that's a non-issue. I did happen to see in a picture what looks to be a flipped exhaust manifold with the turbo in a higher position rather than a lowered position like I've seen in the pickups. Is this standard to your knowledge? I think you're right about the P pumps though, most of the engines seem to be offered in post-94 model busses. Also, are they "de-tuned" you'd say from the P/U CPLs? I'm not looking for huge power gains. I'm just looking for enough umph to move a full size Jeep around and get decent fuel efficieny...or, at least better than the 12 mpg the tired AMC 360 was getting, haha.

Thanks for the info, btw!
 

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It really doesn't matter what engine you go with, the accessories will end up costing about the same, and 99% of all of these conversions will end up "custom" in one form or another. The main thing that I have learned from doing this conversion is, a guy will NOT save money by purchasing a well used engine and fixing it up to be what he wants.

If I had it to do all over again, I would just shell out the money for a new engine. NO mess, NO re-gasketing Hassel. Heck, I'd be done with it by now if I wasn't such a perfectionist :crybaby:.

But then again there are people out there who just throw an old Cummins engine in their project just as it is, oil leaker and all....:puke:
 

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That's good to know. I was planning on using electric fans as well so that's a non-issue. I did happen to see in a picture what looks to be a flipped exhaust manifold with the turbo in a higher position rather than a lowered position like I've seen in the pickups. Is this standard to your knowledge? I think you're right about the P pumps though, most of the engines seem to be offered in post-94 model busses. Also, are they "de-tuned" you'd say from the P/U CPLs? I'm not looking for huge power gains. I'm just looking for enough umph to move a full size Jeep around and get decent fuel efficieny...or, at least better than the 12 mpg the tired AMC 360 was getting, haha.

Thanks for the info, btw!
I dont even think they are detuned. They are just setup more like a semi truck engine. They make boost and power slow and steady for pulling heavy loads long distances. The trucks are tuned to be more "peppy". Actually, the bus engines have more rated power than the early dodge engines....HP and torque. The turbos on some like mine are non-wastegated HX35's with larger turbine housing. This aids in the more sluggish response, but opening up the star wheel helps. Boost controls fuel delivery and visa versa. You can speed the process along with a tighter gated turbine housing or more fuel. More fuel is a free mod:)


The pan, pickup and dipstick tube might have to be changed depending on your chassis. They buses are front sump.
 

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Discussion Starter #8
The sumps are reversible but you will need a new pick up from a dodge.

Gaza
Would the pickup be a standard one from a Cummins Dodge P/U?

Also, has anyone ever thought about going the extra mile and dry-sumping a Cummins? I know of a place that makes custom setups...just a thought for more clearance due to the height of the engine.
 

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I have yet to have a 6b that had a reversable pan. I am not saying that they are not reversable but I know that not all of them are so their must be a design change somewhere in production. You can expect to have considerable more money in an engine from a bus than one from a dodge truck. Lots of minor things that add up in cost in the end, unless you get an engine from a medium duty application dirt cheap and you cannot find one from a truck in the $1500-2500 range. I can also tell you that the oil pans from the first an second gen dodge trucks that I have had will not interchange.
 

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They may be reversable, but the commercial "bus, heavy truck" pan is deeper at 18 quarts than the "Dodge" pickup truck version. It is much to deep and tall to fit for a Dodge truck replacement oil pan, or to fit in my F-350. If I used that pan, the engine would sit too high, and the engine would sit several inches into the firewall just to clear the width of the pan. (Crossmember issues) I will get pics later today to show what I mean (I have both pans at the shop.)

Heres a crude drawing to display what I mean:
 

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Mine was no thicker in the place where you have wrote " too thick for conversion" than a dodge one and did not hang any lower it is about 1/3 of the length rather than 1/4 if that makes sense and yes it is about 15 litres rather than 10 litres for a dodge one. Don't understand why some would reverse and some wont, I thought the 6bt blocks were all the same. On mine I used a dodge pickup and it is fine.

Gaza
 

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There is also a very good chance that your "commercial" pan may yet be a different one than what I am talking about. The 6BT has several different pans from what my parts guy at Cummins Rocky Mountain said.

Heres pics of my "commercial turck" pan compaired to my "Dodge truck" pan:
 

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The 2 pans that John has ( Black is a dodge , oil drain in bottom of pan ) ,the other is a bus pan ,side oil drain plus oil heater 22mm plug.

As far as I know 6 different oil pans

1st gen dodge is different than a 2nd dodge .

Industerial pans come in many different shapes depending on where the engine came from .

Scott
 
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