6.7 with 12 valve rods

ninerqb8

ninerqb8

New member
Joined
Jun 12, 2009
Messages
632
Has anyone put 12 valve rods in a 6.7? I am building a 6.7 and had planned on using 12 valve rods, but I have been told they will hit the cam lobe, and that it will clear just fine. Both answers came from people that I trust would know this information. So has anyone else tried this and know for sure if it will work? This is for stock 12 valve rods not billet rods.
 
I have 12v rods in mine. Lots of 6.7 guys put 12v rods in. If they are glazing the cm the rods need to be flipped around.
 
JL Builders said:
I have 12v rods in mine. Lots of 6.7 guys put 12v rods in. If they are glazing the cm the rods need to be flipped around.
Click to expand...

Did you switch to a narrower lobe cam or the wide lobe 6.7 one? The same person who told me the cam lobes are too wide also told me the rods cannot be flipped or they will hit the block?
 
I run a stock wide lobe cam. Just flipped the rods with out any issues.
 
As others have said just flip them.

The real question is what power level are you hoping for? 12 valve rods will bend rather than break which is a big plus in comparison to the cracked cap rods or you can get a set of these...

IMG_0995_zps1b46a78b.jpg

IMG_0996_zps570cabd7.jpg
 
If high power or RPMs are desired, billet is gonna be your only option. 12v rods have been proven failure points in 6.7s when they start getting turned up. Good to spend it now then bend one and have ti to pull everything apart and start over.
 
I should mention this is going to be p pumped not CR. I dont plan on high rpms or real high timing.
 
12v rods fit just fine in a 6.7. Just turn cap away from camshaft. We have bent several sets of 12v rods in the 6.7. If your running twins, the chance of bending one is much higher than with a big single. We have made over 1000hp with a single charger on those rods as well as the PM rods. The key is the keep rpms up and not lug the engine. Bringing in full boost at low rpm is usually where the failure happens. The rod angle is quite a bit more than in the 5.9 also, so added stress is on the rod. A good way to lessen that is to run a 5.9 crankshaft. There is some work to be done with the piston and block to do so correctly, but its cheaper than billet rods and will give your rods a longer, happier life. pm me for details.
 
Blacksdieselhp said:
12v rods fit just fine in a 6.7. Just turn cap away from camshaft. We have bent several sets of 12v rods in the 6.7. If your running twins, the chance of bending one is much higher than with a big single. We have made over 1000hp with a single charger on those rods as well as the PM rods. The key is the keep rpms up and not lug the engine. Bringing in full boost at low rpm is usually where the failure happens. The rod angle is quite a bit more than in the 5.9 also, so added stress is on the rod. A good way to lessen that is to run a 5.9 crankshaft. There is some work to be done with the piston and block to do so correctly, but its cheaper than billet rods and will give your rods a longer, happier life. pm me for details.
Click to expand...

Thanks but I do want to keep the 6.7 crank. I am not looking for anything over 1000hp but I am going to run twins. Not drag racing or sled pulling just a daily driver.
 
StainlessRRA said:
I'd go billet. A twin turbo 6.7 will crush those rods.
Click to expand...

I would like to but they are just not in the budget. Unless the money for them just shows up in the next 2 weeks before I get it together I am just gonna have to let it fly and hope for the best.
 
ninerqb8 said:
I would like to but they are just not in the budget. Unless the money for them just shows up in the next 2 weeks before I get it together I am just gonna have to let it fly and hope for the best.
Click to expand...

What is your power goal? I guess with the ppump you'll be much safer though.
 
StainlessRRA said:
What is your power goal? I guess with the ppump you'll be much safer though.
Click to expand...

Nothing too crazy. 650 would be good for me. Really I wanted a engine to build and swap into mine so my daily driver would not be down for long and I found the 6.7 for cheap.
 
Oh, at 650 with a ppump you'll be just fine. I was thinking you may be looking for much higher numbers. Guess I should have asked first! I've been wanting to put a 6.7 in mine too, I just can't justify the cost.
 
StainlessRRA said:
Oh, at 650 with a ppump you'll be just fine. I was thinking you may be looking for much higher numbers. Guess I should have asked first! I've been wanting to put a 6.7 in mine too, I just can't justify the cost.
Click to expand...

I am not gonna complain if it end up being more. Only reason I am doing it is because I got a great deal on it. I had planned on doing a a Zeus, with twin pumps etc, but after I added up the cost I changed plans. CR's are way to stupid expensive to build.
 
ninerqb8 said:
I am not gonna complain if it end up being more. Only reason I am doing it is because I got a great deal on it. I had planned on doing a a Zeus, with twin pumps etc, but after I added up the cost I changed plans. CR's are way to stupid expensive to build.
Click to expand...
I run a 5.9 CR with 6.7 crank with 12 valve rods. Over the 1,000hp mark and not a single problem all last year. Running the same ones this year as well.
 
You must log in or register to reply here.
Back
Top