That ZL1 has some power, it just walks away on the straight. Looked like the GTS was making you work for those laps.
If you're using a GoPro Hero5-7, this ND filter set was perfect for properly exposing the tarmac ->
https://www.amazon.com/gp/product/B074V76DWB. I'm using a ND8 and I can now see the tarmac in my recordings vs it being an overexposed white glare.