Something is not right. I can get any of mine to 1000+ degrees with just a level firebox full of charcoal. Make sure the opening in your firebox is lined up with the lower vent opening. Also make sure your charcoal grate is not plugged with small pieces of charcoal. You have to have something restricting the air flow. What kind of lump are you using?

Mike

Know fat, know flavor. No fat, no flavor.

I tried going vegan, but then realized it was a big missed steak.