Without blocking? No, other than driving faster.
@Terence_Dove’s book goes into good detail about opening lap things. I’ve been trying to get some of my drivers to do the same thing. They often have the pace of the top 5, but get shuffled back into the blender on the opening lap because they don’t defend.
It could also be a confidence or mindset thing. Often drivers aren’t able to get into the racing mindset right off the bat in a race, resulting in them driving at 80-90% until they get settled in again. It could just take some laps and practice to get comfortable and get to the limit immediately when the green drops.
I’ve seen countless races won by the 10th fastest kart who just happened to get a good opening lap and settle into their groove immediately while others took time to get up to speed or battled with the pack behind.