Not sure what you have for boots as well, but...
I'm also a larger guy, albeit not as big as you, but I learned a few things quickly.
I'm 6'3" 215 or so, and wear a 13. I ride a GNU 11up 162w. A few weeks ago I bought a 14 mistakenly because it was the best boot for the best money I could find at the time. It was an OLD tech boot, but I replaced them with a brand new size 13 Burton Ambush last week. I never got toe drag or anything, but the newer boots are a ridiculous amount smaller and more comfortable and functional in every way. Newer boots will have the shrinkage tech that makes them smaller on the outside and the same on the inside. That should help you as well!