Here are some of my thoughts regarding my truck,, what do you think?
Registered User
Joined: Mar 2007
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From: Calgary, Alberta, Canada
I'm still putting together a CR engine parts list & procedures that came from discussions on a local CR engine failure/rebuild earlier this year.
While Kevin's race truck is way beyond anything that most of us will ever have, would the forged 12V rods be fine on the street for a good running, dead reliable 600HP CR?
What other reasonable rod options are out there?
While Kevin's race truck is way beyond anything that most of us will ever have, would the forged 12V rods be fine on the street for a good running, dead reliable 600HP CR?
What other reasonable rod options are out there?
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Joined: Jun 2006
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From: Airdrie, AB
Yes, so would stock CR rods.
To expand on this a bit further; the ultimate capacity of CR rods, and 12/24v rods is not significantly different, however the way they fail is. When a CR rod breaks, it quite literally snaps off, and parts go through the oil pan, or block or any other number of places. Typically when a 12v rod "breaks" it just bends, dropping compression in that hole. This is not a 100% guaranteed thing for the 12v / 24v rod, but in most cases holds true. So while it typically isn't a catastrophic failure, it still needs to be fixed as once it is bent it has been weakened and there is no guarantee that it now won't be a catastrophic failure.
IMHO a reliable 600hp common rail (well reliable for a common rail...
) is nothing more then a mid sized single turbo, some injectors, a tune, and a GOOD fuel system away.
To expand on this a bit further; the ultimate capacity of CR rods, and 12/24v rods is not significantly different, however the way they fail is. When a CR rod breaks, it quite literally snaps off, and parts go through the oil pan, or block or any other number of places. Typically when a 12v rod "breaks" it just bends, dropping compression in that hole. This is not a 100% guaranteed thing for the 12v / 24v rod, but in most cases holds true. So while it typically isn't a catastrophic failure, it still needs to be fixed as once it is bent it has been weakened and there is no guarantee that it now won't be a catastrophic failure.
IMHO a reliable 600hp common rail (well reliable for a common rail...
) is nothing more then a mid sized single turbo, some injectors, a tune, and a GOOD fuel system away.
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Joined: Mar 2007
Posts: 1,245
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From: Calgary, Alberta, Canada
Thanks for the excellent info as always Brett. 
Should my engine ever be out of my truck & apart, I'll be tossing my pistons & powdered rods in a dumpster. I don't have time not to...
I should start a new thread on this topic: Bulletproof, reliable CR engine, alleviating all the weaknesses.
Now back to Kevin's truck & engine plans..
Should my engine ever be out of my truck & apart, I'll be tossing my pistons & powdered rods in a dumpster. I don't have time not to...
I should start a new thread on this topic: Bulletproof, reliable CR engine, alleviating all the weaknesses.
Now back to Kevin's truck & engine plans..
Registered User
Joined: Jun 2006
Posts: 954
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From: Airdrie, AB
Thanks for the excellent info as always Brett.
Should my engine ever be out of my truck & apart, I'll be tossing my pistons & powdered rods in a dumpster. I don't have time not to...
I should start a new thread on this topic: Bulletproof, reliable CR engine, alleviating all the weaknesses.
Now back to Kevin's truck & engine plans..
Should my engine ever be out of my truck & apart, I'll be tossing my pistons & powdered rods in a dumpster. I don't have time not to...
I should start a new thread on this topic: Bulletproof, reliable CR engine, alleviating all the weaknesses.
Now back to Kevin's truck & engine plans..
I can build one, in fact I will even have the parts to build exactly that shortly. The downfall of course is it is expensive.
Thread Starter
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From: Fort McMurray, Alberta
My old engine was north of 1100 hp with the stock cr rods, pistons etc. It held fine for years, till a injector hung and I sprayed alot of nitrous then boom. I would not be scared of running cr rods to 7 - 800 hp at all
Thread Starter
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From: Fort McMurray, Alberta
While I agree that I should have billet rods etc, this engine was in a competitive sled pulling truck and survied at over 1200 hp for many pulls. And it wasnt due to failure that I had to rebuild, unless you call a POS owner's lack of maintenance failure.
I would love (and still may if I can find the money) to put in billet rods. But the harsh reality is, that I may not be able too. If this engine goes in a catastrophic way, believe me it wont be a full out race engine going back in, it will be a close to stock engine with my existing bolt ons. 3 grand tops. Run it at about 7 or 800 hp all day long
As for pistons, for sure I will be running the stock pistons, as I know that there is no budget what soever for new pistons. I will get reliefs cut into these ones and then have them coated and call it good.
I would love (and still may if I can find the money) to put in billet rods. But the harsh reality is, that I may not be able too. If this engine goes in a catastrophic way, believe me it wont be a full out race engine going back in, it will be a close to stock engine with my existing bolt ons. 3 grand tops. Run it at about 7 or 800 hp all day long
As for pistons, for sure I will be running the stock pistons, as I know that there is no budget what soever for new pistons. I will get reliefs cut into these ones and then have them coated and call it good.
Where machining and everything becomes expensive, isn't on this block it is WHEN those 12v rods let go. As now you have to find a new block, new girdle, new studs, new rods, new cam, ect...
6.7's Need aftermarket rods period. The torque they develop from the extra stroke is too much for any factory rod past about 800hp.
If this was a 12v 5.9 I would give it a shot as is, they don't typically develop the cylinder pressure, and low end torque a common rail does, and can have full fuel out into the 5000rpm+ area. That and they really aren't that expensive or tough to rebuild.
A common rail is. You are looking at nearly $2000 in just pistons, rings and wrist pins, for a common rail. Even with just stock components, you are looking at nearly $5000 for a mostly stock short block, and that is with you assembling it.
IMHO either get a set of aftermarket rods, or back the horsepower down to 750 - 800.
How light you get it, is purely a function of time available and cubic dollars available.
6.7's Need aftermarket rods period. The torque they develop from the extra stroke is too much for any factory rod past about 800hp.
If this was a 12v 5.9 I would give it a shot as is, they don't typically develop the cylinder pressure, and low end torque a common rail does, and can have full fuel out into the 5000rpm+ area. That and they really aren't that expensive or tough to rebuild.
A common rail is. You are looking at nearly $2000 in just pistons, rings and wrist pins, for a common rail. Even with just stock components, you are looking at nearly $5000 for a mostly stock short block, and that is with you assembling it.
IMHO either get a set of aftermarket rods, or back the horsepower down to 750 - 800.
How light you get it, is purely a function of time available and cubic dollars available.
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From: Airdrie, AB
I am not worried about the pistons.
It is probably the reason they decompressed it as much as they did, it was a way to try to get the rods to live. The 6.7 is a beast when it comes to rods, this is a well documented thing.
At the end of the day, I will just be happy to see it run again, no matter what it has inside of it.
It is probably the reason they decompressed it as much as they did, it was a way to try to get the rods to live. The 6.7 is a beast when it comes to rods, this is a well documented thing.
At the end of the day, I will just be happy to see it run again, no matter what it has inside of it.
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Joined: Mar 2007
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From: Calgary, Alberta, Canada
Sorry to jump in again guys... I am still curious as to what connecting rod options exist for the Cummins CR?
I see the 12V forged rods available everywhere. Mike H. mentioned the 24V VP rods, Kevin mentioned billet rods...
Anyone have some info on rod options they could share?
I see the 12V forged rods available everywhere. Mike H. mentioned the 24V VP rods, Kevin mentioned billet rods...
Anyone have some info on rod options they could share?
Thread Starter
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From: Fort McMurray, Alberta
All rods for a 6BT are useable. The more desireable rods are 12V from Brazil or England (I believe) there are some that use the 24v VP Rods, but IMHO they arent quite as good. As for Billet, there are several companies, such as crower, H&H etc that build aftermarket billet rods
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From: Airdrie, AB
Kevin has it covered.
All rods from 1989-2012, will interchange physically. Most desirable for stock rods are USA built 24v rods and then 12v rods, the only country of origin supposedly to be wary of is Japan, all the others (England, Brazil, Mexico ect...) all seem to be fine.
Early VE rods have a bigger counter weight, but that can be shaved off without much difficulty.
Aftermarket billet rods that I know of are:
R&R (what Torrey runs, and has a couple sets for sale currently)
Cunningham
Crower
Keating Machine
Woodruff Diesel (though there is speculation they just resell someone else's, but they are THE ROD for the big name pulling trucks)
TTS
All rods from 1989-2012, will interchange physically. Most desirable for stock rods are USA built 24v rods and then 12v rods, the only country of origin supposedly to be wary of is Japan, all the others (England, Brazil, Mexico ect...) all seem to be fine.
Early VE rods have a bigger counter weight, but that can be shaved off without much difficulty.
Aftermarket billet rods that I know of are:
R&R (what Torrey runs, and has a couple sets for sale currently)
Cunningham
Crower
Keating Machine
Woodruff Diesel (though there is speculation they just resell someone else's, but they are THE ROD for the big name pulling trucks)
TTS
The Guru
Joined: Jan 2004
Posts: 6,589
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From: Airdrie Canada
All rods for a 6BT are useable. The more desireable rods are 12V from Brazil or England (I believe) there are some that use the 24v VP Rods, but IMHO they arent quite as good. As for Billet, there are several companies, such as crower, H&H etc that build aftermarket billet rods
Still haven't found a shop that actually does shot peen with the proper material and size, most often the material is almost like glass.
I buy R&R rods/monotherms for any motors that I planning on spray heavy. The mains will be billet and I plan on getting a custom gridle built. Running the 14mm ARP main studs at least. Probably be done on a earlier 5.9L CR block.
The Guru
Joined: Jan 2004
Posts: 6,589
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From: Airdrie Canada
Yes, so would stock CR rods.
To expand on this a bit further; the ultimate capacity of CR rods, and 12/24v rods is not significantly different, however the way they fail is. When a CR rod breaks, it quite literally snaps off, and parts go through the oil pan, or block or any other number of places. Typically when a 12v rod "breaks" it just bends, dropping compression in that hole. This is not a 100% guaranteed thing for the 12v / 24v rod, but in most cases holds true. So while it typically isn't a catastrophic failure, it still needs to be fixed as once it is bent it has been weakened and there is no guarantee that it now won't be a catastrophic failure.
IMHO a reliable 600hp common rail (well reliable for a common rail... ) is nothing more then a mid sized single turbo, some injectors, a tune, and a GOOD fuel system away.
To expand on this a bit further; the ultimate capacity of CR rods, and 12/24v rods is not significantly different, however the way they fail is. When a CR rod breaks, it quite literally snaps off, and parts go through the oil pan, or block or any other number of places. Typically when a 12v rod "breaks" it just bends, dropping compression in that hole. This is not a 100% guaranteed thing for the 12v / 24v rod, but in most cases holds true. So while it typically isn't a catastrophic failure, it still needs to be fixed as once it is bent it has been weakened and there is no guarantee that it now won't be a catastrophic failure.
IMHO a reliable 600hp common rail (well reliable for a common rail...
) is nothing more then a mid sized single turbo, some injectors, a tune, and a GOOD fuel system away.The non IC VE rods are the best stock rods available. After that its hard to say if the 12V rods are better than the 24VP rods.
Thread Starter
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Joined: Aug 2006
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From: Fort McMurray, Alberta
If you guys talk to Torrey before I do please let him know to mark one set of those rods for me. I will try to sell the rods I have and put that towards the billet ones. I am also going to see what else I can clear out of my garage to help out on this project, lol