Great video on torque wrench myths being (mostly) debunked:
Yes i liked that bit as the presenter was quite surprised by the zero change at 90 degrees. He showed the adaptor from MotionPro that I have specifically for doing the lower fastners on the Commando head.Anyone who doubts an adapter set at 90 deg. does not change torque reading should see this!
Slick
The amount of anti-seize matters too. I'm mentioned that I use a small amount (pea sized) of nickel anti-seize on the exhaust roses and get about 1/2 extra turn when tightening them. What I didn't mention is that the first time I did it, I used a lot. Got a full turn out of them and then made a MASSIVE mess when the engine came up to temp.Other big take away was the doubling of tension when using antiseize at the same torque setting.
I'd suspect the exhausr roses, being such a big diameter, would not suffer much from over tensioning. It's the loosening off/rattling/vibrations that seem to damage the head threads. I have more concern on smaller fittings, like the head studs & bolts. Putting too much tension from using lubricant/anti-seize without adjusting torque wrench to some lower value would not be good. I believe ARP thread lube for their head bolts comes with an adjusted/lower torque value to use.The amount of anti-seize matters too. I'm mentioned that I use a small amount (pea sized) of nickel anti-seize on the exhaust roses and get about 1/2 extra turn when tightening them. What I didn't mention is that the first time I did it, I used a lot. Got a full turn out of them and then made a MASSIVE mess when the engine came up to temp.
Since I started using it, I've never had one come loose and I've never damaged the threads tightening them.