My tow pig/DD build thread. F350/Cummins 6.7/twins/6R140

me2

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That cover looks nice, but I don't think you are going to "need" it. I have my engine/trans. placement final, well almost and the height is not an issue. I have 1" clearance to the sound dampening material under the hood and that deflects another inch and a half or so. The only issue now is the turbo is touching the HVAC.

I hope you are right and that I don't need it.

However, I think the 08 front end is a couple inches lower than the pre 08 front ends, especially up by the radiator, right where the stock valve cover rises up.

The other issue is that my secondary turbo (HE351) is now probably going to sit on top of the exhaust manifold in some fashion and I'm a bit worried about the heat off the turbine melting the plastic on the valve cover.

We'll see how it all comes together.
 

me2

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I spent a bit of time digging around in Quickserve and online looking for an aluminum (marine) valve cover for the 6.7 that is straight on the inlet side.

I don't think they exist. All the industrial covers seem to have sidecuts in them and some/most use 3 hold down bolts instead of 6.

However, all was not lost as I found other interesting parts, such as a valve cover gasket that works with CM2150 and 2250 ECMs and sidecut valve covers.

I also found out that Cummins makes a 480HP QSB 6.7. The QSB is the industrial version of the ISB. Same basic block and component list, with the gear drive at the back of the engine, so there is more room to run stuff on the front.

QSB 6.7 info is here.
http://cmdmarine.com/engines/rec/inboards/QUANTUM/qsb/qsb-67.html

These two data sheets are interesting.
http://cmdmarine.com/engines/rec/inboards/QUANTUM/qsb/FR93492.pdf
http://cmdmarine.com/engines/rec/inboards/QUANTUM/qsb/FR93731.pdf

I did some parts comparisons between the QSB 6.7 480, an ISB6.7 XT 360 and an ISB 6.7 350/800 and the differences are (much) less than you might imagine.

The HO QSB 6.7 has a flat power curve and makes 450+ HP from 1950ish RPM to redline. Peak torque is 1165 ftlbs at 2000 RPM. From what I can tell via the CPL, working without an ESN, it uses a single HX55 turbocharger that is normally used on a high output ISC 8.3. The HX55 will deliver about 80 pounds per minute. The Dodge Cummins ISB uses the HE351, which tops out at less than 60 pounds per minute.

Suddenly the goal of getting 600HP and 1200 ftlbs from my engine doesn't seem so far fetched.

I am still working on CNC stuff, when I am not taken with family commitments.
 
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Project20v

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Thats a ton of power from a little engine in an industrial application. It is interesting to see the engineers reduced duty cycle requirements for the high power units.
 

me2

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Thats a ton of power from a little engine in an industrial application. It is interesting to see the engineers reduced duty cycle requirements for the high power units.

It takes a ton of power to plow a boat through water. I'd say that the average power useage on a boat engine is much higher than on a (non towing) pickup truck. Its probably the same as a towing pickup truck.

The web page I linked has definitions of each of the duty cycles. The high output duty cycle is defined as the engine running at full power less than 1 in 8 hours of use and less than 500 hours of use a year.

In my spare time I am going to try to get an ESN for a QSB6.7 480 so that I can absolutely compare the parts list to that of the ISB 6.7 XT 360 and the ISB 6.7 350/800. As it stands right now, there isn't a lot of difference. The heads are a bit different, but I think that is mostly emissions. The pistons, injectors and rods are the same.

I'm guessing the reason the QSB6.7 480 doesn't have a lower peak torque RPM is that a) props don't use big torque at low RPMs and b) you can't spool the HX55 at low RPMs.

I like it that the QSB6.7 480 is making nearly 1200 ftlbs, with stock components, one of which is the cracked cap common rail rods. So given enough air, these engines are suitable for making that kind of torque right out of the box.

I wish my friggin parts were cut !
 
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me2

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I'm back. We went on a trip.

I pulled our 5er about 450 miles and travelled about 1000 miles in total. We had a great time.

My F350 got 8 MPG pulling our 5er under ideal conditions, which I think is terrible. It got about the same fuel economy pulling the trailer on the Father's Day weekend as well.

My '99 (5.9CR + ZF6) got 9.5 MPG at worst, in bad conditions (rarely) and usually got 10.5 to 11.5 MPG pulling the same trailer, on the same route at the same speed.

The other issue my F350 has is ride quality, especially when pulling our 5er. My wife and I, both healthy people, both had sore backs the day after we got home.

I've got some work to do on this truck before I am going to be totally happy with it.

On the project side, I'm still waiting for CNC plasma table parts.
 

skipped_link

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I'm back. We went on a trip.

I pulled our 5er about 450 miles and travelled about 1000 miles in total. We had a great time.

My F350 got 8 MPG pulling our 5er under ideal conditions, which I think is terrible. It got about the same fuel economy pulling the trailer on the Father's Day weekend as well.

My '99 (5.9CR + ZF6) got 9.5 MPG at worst, in bad conditions (rarely) and usually got 10.5 to 11.5 MPG pulling the same trailer, on the same route at the same speed.

The other issue my F350 has is ride quality, especially when pulling our 5er. My wife and I, both healthy people, both had sore backs the day after we got home.

I've got some work to do on this truck before I am going to be totally happy with it.

On the project side, I'm still waiting for CNC plasma table parts.

Sounds like you should have got a medium duty truck with a cummins & air ride already installed.
 

me2

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I don't want to turn this thread into a MDT versus pickup debate. I'll reply to this and lets leave it at that.

I grew up around MDTs and I hate them. Under powered, rough, noisy, geared wrong for highway use and I don't see any need to use a MDT to pull a 14,000 pound trailer.

And there is no way an MDT would work for my DD needs, nor for my family's adventure travel needs. My F350 works great in this respect.

An MDT would actually cause me a great deal of grief. An M2 weighs about 12K, depending how you fit it. My trailer weighs just under 14K. The two together would put me right at 26K and then I would have to start thinking about getting a CDL for me and my wife. With my F350, the truck and trailer weigh 22K, so I have some margin.

For the record, I spec'd out an M2 crew cab before I started this project.
 

Mark Kovalsky

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An M2 weighs about 12K, depending how you fit it. My trailer weighs just under 14K. The two together would put me right at 26K and then I would have to start thinking about getting a CDL for me and my wife. With my F350, the truck and trailer weigh 22K, so I have some margin.
Only if you are using the rig to make money. If you are using it only as an RV it doesn't matter what the weight rating is, no CDL required.

And actual weights do not enter into the need for a CDL. It is all weight rating. If the rig together weighs 24k, but the two gross vehicle weight ratings total over 26k, or the trailer GVWR is over 10k, AND they are being used for commerce, you need a CDL. Private use, no CDL.
 

me2

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Only if you are using the rig to make money. If you are using it only as an RV it doesn't matter what the weight rating is, no CDL required.

And actual weights do not enter into the need for a CDL. It is all weight rating. If the rig together weighs 24k, but the two gross vehicle weight ratings total over 26k, or the trailer GVWR is over 10k, AND they are being used for commerce, you need a CDL. Private use, no CDL.

It depends on the jurisdiction. Every one seems to be different and with the prominence of large Rvs, some are changing the rules, adding a special license for rvs.

http://changingears.com/rv-sec-state-rv-license.shtml

Insurance is another story as well.
 
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Jake

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Is this truck single wheel or duals ? Just curious for air ride fitment

Sent from my DROID RAZR using Tapatalk 2
 

me2

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I haven't seen this valve cover before.. Seems to have a different bolt arrangement though.

http://www.cumminspowersouth.com/logging.html

Good find.

Great, now I have to go find another engine serial number !

That cover uses 3 bolts. A stock 6.7 cover uses 6. The 5.9 marine cover uses 6.

I don't think it would be hard to machine the rocker arm spacer thingy to use 3 bolts.
 

Hotrodtractor

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You know guys - valve covers are really easy to make... especially if you need just a little bit of clearance in a location and it doesn't actually interfere with any of the valve train. Just a little food for thought.

318122_10150773428530876_709806607_n.jpg
 

Hotrodtractor

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Sweet!! i was going to ask that.. BUT I can see through it... I did not know you could see through Cardon fiber...

Light but strong!! I am guessing that is not a cheap route...

You are seeing a reflection.

Yes - carbon fiber is not cheap - but you can make valve covers out of anything - I just used it as an example of something different. The next set of custom valve covers I do for myself will be carbon fiber.....
 

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