Assuming well pre-heated oven.
Top and Bottom
140 = 155
150 = 160
160 = 170
165 = 175
170 = 215… 180 after 10
175 = 210… 185 after 10
180 = 205 – 210 (slowly up to 210, where it settles.),… But then settling at 190 after 10 minutes… A total shit show.
190 = 210 (… Yep… Seems quite happy to be at 210, same as 180. Possibly gets there faster.)… Another try gives me 200.
200 = 230… Then 210 on another try
210 = 240… Then 220 – 225
I think upon reaching temperature initially, the oven will overheat due to the energy put into getting there from room temp. Then over time (more than 10 minutes) it will gradually become more accurate, seemingly just about 10c higher than the desired temp. It’s possible that over a longer period it simply becomes 100% accurate, but I’ve not yet tested this. So… The shorter the bake, the more inconsistent the temperature. Also if starting from hot already, the results will be different than if starting from cold. Which explains some of the inconsistencies.