In 2018 Walls jumped into a single seater car for the first time competitively with the Patrizicorse team in the Australian F4 Championship.http://www.formula4.com.au/?p=12296 A string of successful midfield results as well as 3 podium finishes put him 6th with 148. Walls returned for the next campaign and his results were similar to the previous year, he took his maiden career victory at Tailem Bend, Lochie Hughes who started on pole initially took the victory after taking the lead back from Walls. Contact with Ryan Suhle caused the stewards to award Hughes with a 5 seconds penalty, allowing Walls to take the top step of the podium.
