Which scale? THC apparently vaporizes at 360 degrees F. You want it to vaporize, but you don't want to heat it any more than that than possible. I'm pretty sure that vaporized THC is transparent, so if you see a lot of smoke you are burning the plant matter. Adjust accordingly and experiment. If you folks mean 170 C, you're probably in the right region.
It all really depends on your style of use too. If you let the heat build up in the chamber and then just inhale what builds up in the chamber, then the temp of the element will be the same as the temp of the air.
But if you draw air across the element in a long slow inhale, then the air will be significantly cooler than the element and the air will additionally cool the element-- so you need to start with a higher temp.
