Sounds to me that the charcoal you use is full of fines and charcoal dust. Dumping straight from the bag then clogs the intake holes. Perhaps the turbo vent will allow you to do that and not stifle the fire.
You could try a better brand of lump, even with the turbo grate, to get a cleaner burn.
Jim - Another transplanted Texan
Former KCBS CBJ
Large and Medium Big Green Eggs , Black 18.5" WSM, Blue Weber Performer - Stainless, Green Weber OTG Kettle , Brinkmann SnP Pro, and a Stainless UDS. One retired Portable Kitchen grill.
Red Thermapen, Maverick ET-732, EdgePro Apex Sharpener.
Avatar is the original 1951 Weber Kettle