V8 Supercars young guns Scott McLaughlin, Chaz Mostert and Nick Percat have upset their experienced rivals to top practice at Queensland Raceway on Friday.

Volvo driver McLaughlin posted the fastest time of the day in the third 20-minute practice run at Ipswich, clocking a best lap of one minute and 09.7256 seconds on the 3.12km circuit.

Ford driver Mostert, a winner at Ipswich last year, was second in 1:09.7637 while former Bathurst winner Percat posted a 1:09.8114.

Championship leader Mark Winterbottom clocked the day’s sixth best time to be the leader of the title contenders.

Main rival Jamie Whincup was eighth-fastest while veteran Craig Lowndes could only clock the day’s 11th quickest time.

The Ipswich 400 kicks off on Saturday with two 100km races before a 200km main race on Sunday.