How much of a difference do NA mods actually make?

Racing my modified Mustang GT against the stock version of itself to see how much of a difference naturally aspirated mods actually make. We also both race a Porsche 911 and the results are surprising! You can get in contact with me (and find my store, socials, etc) through my Tazet profile: Also consider checking out AvalonKing’s ceramic coating kit: They aren’t sponsoring this video, but this stuff has been kind of magical. I will never not ceramic coat any of my vehicles from now on. See my previous video for detailed info / instructions: