do these have a torque spec? (pic)

[weider1717]

Do these nuts thats spring preloaded have a torque spec? I asked this a few weeks ago and someone said 18 ft lbs but I have them where it was at originally (by looks) and the torque wrench didn't even click at 5 ftlbs.

this is the bottom side of the manifold there it mates to the exhaust pipe so it's clear to you. Again this isn't even 5ft lbs and the springs are very much preloaded so I'm not sure here so asking again.