Surprisingly in-depth article from Jalopnik on NASCAR cooling systems, cooling drag, grill blocking (with tape!), and intake air temperatures:
https://jalopnik.com/the-fascinating...hot-1835071544
The article was spurred by this video, where you can see some of their ducting setups, etc.:
https://www.youtube.com/watch?time_c...&v=3LuS7eK3o64