As we have tracked runs on our TBrake equipped low 11 sec SBC Chevelle we are seeing close to the 100'/ .01 change. Not changing setups, parts or routines was key to getting 'good' data for us. We currently use at track calculated DA and wind speed/direction at the start of the track. Which driver was in the car as I am about 50# heavier than Dad, along with tires pressure, launch and shift rpm and engine and trans temp at turnout of the lanes. Looking to add a data recorder this winter to dial in our program as well.
Here is a link to a pretty good article on the topic from Hot Rod. I will give that Hale's Jr Website a go sometime soon to hopefully gain some more insight.
https://www.hotrod.com/articles/ccrp...ensity-tuning/