Subject: What is hotter, a small 'oven' or a larger one?

I.e. if one constructed two simple ovens/kilns (say just a brick structure 
with fuel at bottom), one twice the size of the other (say a cube and an 
oblong size of two cubes), and the larger one is heated with twice the amount 
of fuel, which would be hotter. I ask because in reality i THINK the smaller 
one is hotter, but surely the larger one should be since it has less surface 
space per volume to loose heat. Does doubling the fuel double the 
temperature?? Where have I gone wrong, if I have!? Thank you for you help.

Re: What is hotter, a small 'oven' or a larger one?