Torque reduction with use of loctite?

[Cubieman]

I have been trying to find some solid information in regards to torque numbers and the usage of loctite. Some people say to reduce torque value by 20% similar to torquing with lubricants and some say this isn't necessary at all.
In my mind locite is definitely a lubricant while it is setting up so wouldn't reduction be necessary?
This is getting in the weeds a bit, however I know we have some smart people on here and just interested in getting a bit more information.

Thinking of pulling my 12.9 grade Lang cam bolts out and installing new bolts torqued to 12ft lb as opposed to the 9ft lb I used. But with the threads covered in loctite and thinking about what to set the wrench to I'm getting myself all confused, again, go figure.

[Zack]

Loctite isn't something I like using in an engine personally. As an Auto Technician I prefer to use what was installed from the factory be it thread sealant, thread locker, or nothing at all. If it were necessary to keep things secure it would have been used during production. As for the torque reduction, I would say no. The possible "overtightening" you are thinking may happen will be negligible at best. At worst you have fasteners that are inadequately tightened leading to undesired movement.

[Cubieman]

Loctite isn't something I like using in an engine personally. As an Auto Technician I prefer to use what was installed from the factory be it thread sealant, thread locker, or nothing at all. If it were necessary to keep things secure it would have been used during production. As for the torque reduction, I would say no. The possible "overtightening" you are thinking may happen will be negligible at best. At worst you have fasteners that are inadequately tightened leading to undesired movement.

It has been established that the use of loctite is a very good idea with the Vanos cam bolts as they can back out potentially causing serious issues.

My issue is I can't decide whether or not to reduce the torque because of loctite if I decide to pull them out and install new ones torqued to 12ft lb instead of 9ft lb.
It's funny...if I did a 20% reduction of 12ft lbs, it ends up damn near the 9ft lb they are currently torqued to.

[eacmen]

I have been trying to find some solid information in regards to torque numbers and the usage of loctite. Some people say to reduce torque value by 20% similar to torquing with lubricants and some say this isn't necessary at all.
In my mind locite is definitely a lubricant while it is setting up so wouldn't reduction be necessary?
This is getting in the weeds a bit, however I know we have some smart people on here and just interested in getting a bit more information.

Thinking of pulling my 12.9 grade Lang cam bolts out and installing new bolts torqued to 12ft lb as opposed to the 9ft lb I used. But with the threads covered in loctite and thinking about what to set the wrench to I'm getting myself all confused, again, go figure.

What torque value does Lang recommend?

[Cubieman]

What torque value does Lang recommend?

I emailed Andrew Lang:
The 9ft lb will be sufficient although you could go to 12 next time and it would be just fine. The loctite will ensure they don’t loosen up.

They supply the red loctite, and I used the Blue 243 stuff, that I did not mention to Lang. I am waiting on a new valve cover so I thought if there was any benefit to pulling the bolts and torquing higher I will do it, don't want to have issues down the road. The OEM bolts are 8.8 and have a torque spec of 9ft lb but the Torque spec for a 6mm 12.9 grade bolt is 12ft lbs according to the torque spec master document that is stickied.

[eacmen]

I emailed Andrew Lang:
The 9ft lb will be sufficient although you could go to 12 next time and it would be just fine. The loctite will ensure they don’t loosen up.

They supply the red loctite, and I used the Blue 243 stuff, that I did not mention to Lang. I am waiting on a new valve cover so I thought if there was any benefit to pulling the bolts and torquing higher I will do it, don't want to have issues down the road.

If the vanos is installed I would say leave it as is. The blue loctite should be good enough.

Let’s assume that you do need to reduce torque by 20% with loctite, then 12*.8=9.6.... so pretty darn close to what you already did.

[Cubieman]

If the vanos is installed I would say leave it as is. The blue loctite should be good enough.

Let’s assume that you do need to reduce torque by 20% with loctite, then 12*.8=9.6.... so pretty darn close to what you already did.

That's sure how I would like to look at it.