nope defo open on start up I checked standard and my scorpion they are open on tickoverI'm pretty sure that they're closed on startup judging by how soft it is. The Milltek valves work exactly the same as stock valves and it's definitely quieter on start up. I think the valves are linked to both throttle position and rpm. Except in dynamic it opens earlier. It's pretty easy to tell when the valves are open because it sounds muffled.