You want a SMALL hot clean fire. Allow time for the pit to warm up at least 1 hr once it is hot the temp is easier to maintain. So in the beginning build a little bigger fire to get a good coal base then feed it at a rate to maintain the temp Zone. Don't fight trying to Maintain
a temp, cook in a Zone for me it is between 275 & 325. Control your temp with the fire mass and the smoke with the intake damper.( Less air heavier smoke colder fire) It's like adjusting a Carburettor on a Corvette. Once you have the fuel and Air in balance
it will just cruise.