2000g sourdough boule in medium sized dutch oven
Weak ovens still get to needed temperature, but slower and/or they may "leak" heat. The only way around it is to "accumulate" heat by placing baking stone into the oven, and (Thanks to Alton Brown creativity) place upside–down large clay pot around the bread. Naturally, you need to pre–heat them before you place the dough in.

Stone and clay keep heat much better then steel your oven is made of. Also, they distribute it more evenly.

This technique is similar to baking in a dutch oven.