IndyCar is known for its close, action-packed races with Dallara-built cars that are largely spec outside damper development and having two different engine manufacturers.
It leads to very close racing, with top six qualifying shootouts on several road courses covered by three tenths or less.
In its 2023 opener at St Petersburg, there was a three-tenth difference between leading the first phase of qualifying and being eliminated in the group stages altogether.
F1 has had similar tight qualifying sessions in 2023, with the field being brought closer together thanks to the budget cap and teams converging on similar aerodynamic designs.
But while IndyCar has enjoyed seven different race winners across four teams, race day competitiveness has been a different beast in F1, with Red Bull winning all but one of 2023's 22 grands prix as Max Verstappen walked to his third straight world title.
According to Brown, who fields teams in both series, F1 is not miles away from reaching an IndyCar level of convergence as the current technical regulations carry on into 2024 and 2025.
"If you look at the timesheets even these teams that are ninth and 10th [in the standings] are a threat for Q3," Brown said.
"For the championship, it's probably going to be the same cast of characters, but I think Formula 1 is going to get more competitive.
Source: Autosport