Spark plug installation torque, with/without anti-seize?

[prwood]

I've seen the tightening torque for the spark plugs in my V70 listed as both 25 Nm and 30 Nm. I've also seen instructions to install with and without anti-seize lubricant. There's already plenty of debate elsewhere over whether or not to use anti-seize to begin with, so that's not my question here. I also know that using anti-seize decreases the amount of installation torque needed. However, I wanted to try to confirm what seems to be logical and appears to be implied in some places, but which I haven't seen explicitly stated: that the 25 Nm torque is for when anti-seize is used, and the 30 Nm torque is for use without anti-seize. Bonus points if someone has a link to a document that explicitly states that.

I would love to say that there's probably not much difference between 25 and 30 Nm, or that I should just use some rule-of-thumb or common sense to tighten the spark plugs, except for the fact that in a previous car, I snapped a spark plug off inside the cylinder head after applying too much torque.

[Georgeandkira]

Stick with the book on torque and do it dry and you'll be in the clear.

I shrieked in horror as the plugs in my first V70 howled and chattered upon removal. I have used copper anti-seize ever since.
A plug with a crush washer takes a 1/4 turn-90º-after contact.
Old iron heads claimed 1/8 turn-45º-for gasketless plugs after contact.
On our aluminum heads I do half that-1/16 turn-22º.
ALSO: Now when I remove them I simply crack 'em loose I spray some Kroil (or other penetrant) down the access tube, let it sit and work the plug back and forth. The very last thing I want is the aluminum threading to gall.

Never had a problem. And I'm not telling you what to do as I don't want to be sucked into the maelstrom.

[abscate]

There is some conflict in VIDA here. Spark plug torque on my slightly superior 99 is given as 25 Nm, but then.....

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So I would lube and use 30Nm , which is probably in the error bar of your torque wrench, anyhow.

Most inexperienced mechanics will overtorque 30Nm, it isn't that tight.

Use cheapie copper plugs in your Volvo, replace every 30k to avoid the shrieks of neglect.

And, lament that Prince didn't write a song about your car

[jonesg]

The only problem I had in alum was after an overheat blown hose. Other than that, no problem with or without anything on the threads.

[abscate]

You can get pretty close to torques with

Wrist choked up on 6 inch ratchet...10 ft lbs
Wrist muscles on ratchet end...20 foot pounds
Forearm on 6 inch.............50 foot pounds
Arm at full strength 75-100 ft lbs

I'll confess I don't use a torque wrench on plugs, I go by feel. Next time I'll check myself to see how close I am