What temps are you wanting to cook at? I cook at 300 My drum is constructed just like yours with the exception of all my intakes are 3/4" I start with a Full basket of lump and dump a 1/2 a hot chimney on top. And wait 10 min before dropping it in the drum with all intakes open. At 250 I cap 1 and close the ball valve by 1/4 it settles in at 300 on the button. I'm cooking with in 20 min from light up. Sometimes it will creep up 25 deg but I'm fine with that. Adjustments normally take about 15 min to show up on the thermo. For what is worth the West Tx wind never quits blowing I guess because of all the Suckers in DC.
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