Motor Build time 5.9 or 6.7

dnrcustoms

dnrcustoms

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If you were to build an all out Cummins Motor, what would it be and Why? 5.9 or 6.7 Im on the fence, not sure if I want to go for the torque monster of a 6.7 or the tried and true 5.9. Building for 1000-1200hp on Fuel, 1300+ on Juice. I think a 5.9 will be easier on parts spinning more rpm. Using 200% 6.7 injectors, Billet rods, 14mm mains, Billet Cam, 14mm Head studs, Dual Pumps, Side Draft, Ported 6.7 head, all the goodies. Either large twins or Triples for chargers Going in the Blue Balled Nightmare!!

Pretty sure I am going with Monster Mike on the Machine work, going with his custom Girdle that is machined into the block,

Already built a wicked 6.7 destroked motor using a 5.9 cranks and loved it, but I went with ARP 12mm mains and had a failure. So, back at it again looking for a little advice. Truck will mainly be used for Drag racing on the street and sand. Some Exhibition Sled pulling. Thanks
 
What was the failure with the destroked 6.7 build. Looking at building one right now myself.
 
Well, I had a Event I was scrambling to get it done for, didn't have time to do 14mm mains, used 12mm arp. It blew the nuts right off 4 3 2 1 with the threads still in the nut then broke my crank also junking my block. After doing some research I was told the arp 12mm are to short and I was better off using factory bolts. So lesson learned I guess. I used a 5.9 crank in a 6.7 block and we took .080 off the deck. Motor ran great while it ran, It pulled hard to 3800-4k
 
dnrcustoms said:
Well, I had a Event I was scrambling to get it done for, didn't have time to do 14mm mains, used 12mm arp. It blew the nuts right off 4 3 2 1 with the threads still in the nut then broke my crank also junking my block. After doing some research I was told the arp 12mm are to short and I was better off using factory bolts. So lesson learned I guess. I used a 5.9 crank in a 6.7 block and we took .080 off the deck. Motor ran great while it ran, It pulled hard to 3800-4k
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Cool any pics? When you blew the main studs did you have billet rods in?
 
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Ya, Had Corrilo Rods, brand new!!
Before!!
[ame="http://s132.photobucket.com/user/dnrcustoms/media/SNOWFLAKE/D096B47D-7203-4719-8DA4-81570428033B-4124-000001DB6629C384_zps8c11227e.jpg.html"]D096B47D-7203-4719-8DA4-81570428033B-4124-000001DB6629C384_zps8c11227e.jpg Photo by dnrcustoms | Photobucket[/ame]
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[ame="http://s132.photobucket.com/user/dnrcustoms/media/SNOWFLAKE/B54E0D2D-5943-4FA7-97BA-E63C23EBFC09-3604-0000019F226CD78B_zpsdfe558a1.jpg.html"]B54E0D2D-5943-4FA7-97BA-E63C23EBFC09-3604-0000019F226CD78B_zpsdfe558a1.jpg Photo by dnrcustoms | Photobucket[/ame]
[ame="http://s132.photobucket.com/user/dnrcustoms/media/SNOWFLAKE/D1E306D0-81F6-48D1-A9AC-52E3607D948E-3604-0000019FAAF00531_zpscdd6e2b5.jpg.html"]D1E306D0-81F6-48D1-A9AC-52E3607D948E-3604-0000019FAAF00531_zpscdd6e2b5.jpg Photo by dnrcustoms | Photobucket[/ame]
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[ame="http://s132.photobucket.com/user/dnrcustoms/media/SNOWFLAKE/1D1858AA-CB3D-49B9-9F73-99EC35D6B5AE-3604-0000019EAC98FC5E_zpsc4793b3c.jpg.html"]1D1858AA-CB3D-49B9-9F73-99EC35D6B5AE-3604-0000019EAC98FC5E_zpsc4793b3c.jpg Photo by dnrcustoms | Photobucket[/ame]

Click for video[ame="http://s132.photobucket.com/user/dnrcustoms/media/SNOWFLAKE/D01D8238-2E4C-4702-928F-FAD4B436BF9D-3604-0000019FF167BC36_zpsfb9070a3.mp4.html"]D01D8238-2E4C-4702-928F-FAD4B436BF9D-3604-0000019FF167BC36_zpsfb9070a3.mp4 Video by dnrcustoms | Photobucket[/ame]
 
In the one pic where there is still a nut on the main stud....it looks like the stud doesn't stick out of that nut. I really wonder as even the 12mm main studs are supposed to stick out of the nuts, being fully threaded, requiring the factory block stiffener to be clearanced. Was this a bad stud production run or an assembly dynamic..as in were the holes blind tapped allowing the studs to sit down 3 threads further in the holes? Just thinking out loud..
 
i have a feeling those studs break from power. there was likely another issue. cranks dont break on these motors unless somethings REALLY unhappy.
 
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I'll say this, you get an 8.5 out of 10 in the carnage department.
 
I say u go with the 5.9, there alot easier to build so ive heard.
U need a build thread, thatd be sweet!
 
well, I was super busy in the shop. pd the machine shop to assemble the short block since they had everything there anyway. I got it and the girdle was on. I feel the stud wasn't protruding the nut at all, I was told the ARP mains are two short when seated fully into the block, obviously after the fact. Also, My guess is it popped #4 main nut first, then 3 2 1 then the crank was wobbling like a mofo then broke at #1 cause their was no support left..

Moving on from my carnage cause I really don't want to talk about it for obvious reasons, lol What are some thoughts on the build? Maybe even 6.4 again?

Below is a pic of my first motor!! 900+ single S480 and stock Cr rods. Its been a rough summer!!
[ame="http://s132.photobucket.com/user/dnrcustoms/media/SNOWFLAKE/IMG_8763_zps951a5267.jpg.html"]IMG_8763_zps951a5267.jpg Photo by dnrcustoms | Photobucket[/ame]
[ame="http://s132.photobucket.com/user/dnrcustoms/media/SNOWFLAKE/IMG_8762_zps8ec145ed.jpg.html"]IMG_8762_zps8ec145ed.jpg Photo by dnrcustoms | Photobucket[/ame]
[ame="http://s132.photobucket.com/user/dnrcustoms/media/SNOWFLAKE/IMG_8412_zps58dc7ce8.jpg.html"]IMG_8412_zps58dc7ce8.jpg Photo by dnrcustoms | Photobucket[/ame]
 
Rough summer indeed, I hate those surprise crank inspection windows.
 
StuckinMud said:
In the one pic where there is still a nut on the main stud....it looks like the stud doesn't stick out of that nut. I really wonder as even the 12mm main studs are supposed to stick out of the nuts, being fully threaded, requiring the factory block stiffener to be clearanced. Was this a bad stud production run or an assembly dynamic..as in were the holes blind tapped allowing the studs to sit down 3 threads further in the holes? Just thinking out loud..[/QUOT

I have the same studs in my motor and they portured more then yours do. Kinda has me second guessing then now.
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chance cobb said:
StuckinMud said:
In the one pic where there is still a nut on the main stud....it looks like the stud doesn't stick out of that nut. I really wonder as even the 12mm main studs are supposed to stick out of the nuts, being fully threaded, requiring the factory block stiffener to be clearanced. Was this a bad stud production run or an assembly dynamic..as in were the holes blind tapped allowing the studs to sit down 3 threads further in the holes? Just thinking out loud..[/QUOT

I have the same studs in my motor and they portured more then yours do. Kinda has me second guessing then now.
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There were only 1-2 threads on a few of thr nuts, most were just above flush. If i would have put it together. I would have cought it. Rule of thumb is like 4-5 threads i believe. Just look how much longer custom age 625 head studs are than the 425s. At least 3-4 threads extra.
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Yeap, you definitely get the award. Haven't had one of you guys in a while. Ever since Swole ended his carnage.
 
Ya, Im not looking for any awards!! lol This whole Project has been a Night mare, Called Project Blue Ballz

Here is what it looked like when I started back in Dec Of 2012
[ame="http://s132.photobucket.com/user/dnrcustoms/media/SNOWFLAKE/18EF7B2B-185E-474B-9B74-B8487B1A2C09-3265-0000036950BA01B9.jpg.html"]18EF7B2B-185E-474B-9B74-B8487B1A2C09-3265-0000036950BA01B9.jpg Photo by dnrcustoms | Photobucket[/ame]
[ame="http://s132.photobucket.com/user/dnrcustoms/media/SNOWFLAKE/2D6EBB8C-B9D8-4357-9BE9-21EFE7340683-3265-000003691665ECBD.jpg.html"]2D6EBB8C-B9D8-4357-9BE9-21EFE7340683-3265-000003691665ECBD.jpg Photo by dnrcustoms | Photobucket[/ame]
[ame="http://s132.photobucket.com/user/dnrcustoms/media/SNOWFLAKE/2BFC1C18-E923-4518-B320-91BBBC24FF1E-3265-000003692648C6D5.jpg.html"]2BFC1C18-E923-4518-B320-91BBBC24FF1E-3265-000003692648C6D5.jpg Photo by dnrcustoms | Photobucket[/ame]
 
No need to be scared of the mains. We run stock main bolts and girdle at over 1400hp in our 6.4 and 6.7 and have never had any failures.

I vote 6.4 baucse you have so many options on how to set it up. This can also be a bad thing for some.
 
Blacksdieselhp said:
No need to be scared of the mains. We run stock main bolts and girdle at over 1400hp in our 6.4 and 6.7 and have never had any failures.

I vote 6.4 baucse you have so many options on how to set it up. This can also be a bad thing for some.
Click to expand...

What is involved in building a 6.4?
 
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