Rollout vs ET

If I’m not mistaken and maybe I am, the clock starts when your tire leaves the second ‘Staged’ beam right? So, staging shallow plus the distance between the two beams would be a lot more than 6 inches wouldn’t it?
I didn't measure it. 8" ?? What's the size of your front tire, that plays a big part too. AND, how much tire pressure?? A tire that's low on pressure will stay staged longer. I wasn't including all the variables, I was only answering the question I was asked by motorpirate - the purpose of a rolling start.