I have a friend with a gto, I've been tweaking his tune a little here and there trying to make it run more consistent. It was dyno tuned before he bought the car but it won't run same times to save its life. He uses it for bracket racing. I made a few changes and was able to run the exact same times 4 times in a row hot lapping. But during normal racing he has long breaks between runs. It will run same same for a while and suddenly jump .1 in the 1/8th. Which can cause a break out and a loss.
Only thing I can think of is the maf. He does randomly get maf fail CEL every once in a while some times at the track some times on the street. It's been cleaned and what not.
I'm on my phone so I'll post some logs and tune later. It's an 04 gto ls1 auto. He does run drag radials and it's basically a stock motor with long tubes and an intake. He isn't looking for power so much as just being consistent.