So I did a test tonight as I am working towards my first ever smoke.. I have a 18 inch Weber Silver Touch and I decided to test some temperature while I was grilling dinner tonight just to see what was what. So here is exactly what I did. 1. Filled chimney about half way to maybe a little more than half. Lit fire with paper underneath 2. Waited 20ish minutes for the coals to do their thing. 3. Fire was coming out of top of chimney at 20ish minutes but top coals were very slightly ashed. 4. Dumped coal on one half of grill. 5. Seared a steak for a total of about 4 minutes. Left vents open for that 6. Moved steak to non coal side 7. Cooked a Lemon Pepper Catfish over hot coals. 8. Put lid back on and closed top vent on a long probe thermometer that I use for beer making. 9. Waited about 5-10 minutes. Probe was in maybe an inch or so with vent closed on it. 10. Temperature was about 450 or so on non coal side 11. I closed bottom vents to about 50% 12. 10 minutes later temperature was about the same. So what did I learn? Not quite sure which is why I am asking you folks. Should I use half or less coals and close top vent once I put coals on one side?