[HFR_Racer]

Yes.. That is one strong M8 jamb nut.. I would've figured that the jamb nut threads would've pulled out versus the adjustment bolt. I would say that the torque figure would be ok if you use a full nut, but since it's a half nut I would imagine that the torque value should be reduced. I'm highly confident that if I put 20 ft-lb on the jamb nut for all of my rockers then 90% + will fail the threads. Therefore, 20 ft-lb is no good for me..

Also, you can easily torque these using a torque wrench. I simply used a 3/8" drive in-lb torque wrench with a 6" extension. I probably could've used a 3" extension but my knuckles would be pretty close to the valve cover studs.

I'm not at all sure why your thinking that a torque wrench can't be used on the jamb nut for the valve adjuster bolt??