A late switch of engineers has failed to stop Chaz Mostert continuing Prodrive’s fine form, topping opening practice at a rain hit Symmons Plains Raceway.

The Pepsi Max Ford driver emerged ahead after all of the eventual front-runners set their best times in the final minutes.

The 22-year-old’s car is being run by the team’s engineering manager Nathaniel Osborne this weekend while Adam De Borre attends an urgent family matter in the United Kingdom.

Mostert’s 1:02.28s best put him just 0.02s clear of second fastest man Will Davison, with the times over 11s adrift of the practice lap record.

“If the weekend is wet then fingers crossed we’ll be up the pointy end,” said Mostert post-session.

“It’s a good way to roll out coming off the grand prix after a string of second places.”

Shane van Gisbergen, Jason Bright, Jamie Whincup, Scott McLaughlin, David Reynolds, Mark Winterbottom, Fabian Coulthard and Rick Kelly completed the top 10.

All 10 drivers undercut an earlier time that had seen Coulthard on top when red flags flew to retrieve McLaughlin’s Volvo from the Turn 4 gravel with 11 mins remaining.

A wet track had greeted drivers for the start of the 60 minutes, with the rain proving relatively consistent throughout.

An early effort from Winterbottom put his Prodrive Ford at the top of the order for much of the session as conditions worsened in the middle stages.

“It was really hard to read the conditions,” said second fastest man Davison.

“You’d make a set-up change and then it would rain harder or ease off, so it was hard to gain anything.

“But it was full-on. It’s a tricky little place when the conditions are like that. It was pretty hairy.”

Despite the tricky conditions, the red flags were called just twice. The first came when an oil pressure problem stopped Brad Jones Racing’s #21 Holden in the opening minutes.

Dunlop Series driver Macauley Jones shared the car with its primary driver Dale Wood, while BJR also elected to give Fabian Coulthard’s co-driver Luke Youlden laps in its sister entry.

Scott Pye meanwhile ended the session 18th as his ‘co-driver’, Marcos Ambrose, watched on from the garage.

A second 60 minute session will take place from 1325.

Result: V8 Supercars, Practice 1

1

Pepsi Max Crew

Chaz Mostert

Ford Falcon FG/X

1:02.2774*

2

Erebus Motorsport V8

Will Davison

Mercedes E63 AMG

01:02.30

00:00.02

3

Team Darrell Lea STIX

Shane Van Gisbergen

Holden Commodore VF

01:02.39

00:00.11

4

Team BOC

Jason Bright

Holden Commodore VF

01:02.58

00:00.30

5

Red Bull Racing Australia

Jamie Whincup

Holden Commodore VF

01:02.61

00:00.33

6

Wilson Security Racing GRM

Scott McLaughlin

Volvo S60

01:02.66

00:00.39

7

The Bottle-O Racing Team

David Reynolds

Ford Falcon FG/X

01:02.71

00:00.44

8

Pepsi Max Crew

Mark Winterbottom

Ford Falcon FG/X

01:02.73

00:00.45

9

Freightliner Racing

F.Coulthard/L.Youlden

Holden Commodore VF

01:02.79

00:00.51

10

Nissan Motorsport

Rick Kelly

Nissan Altima

01:03.00

00:00.72

11

Red Bull Racing Australia

Craig Lowndes

Holden Commodore VF

01:03.10

00:00.82

12

Team Cooldrive

Tim Blanchard

Holden Commodore VF

01:03.16

00:00.88

13

Holden Racing Team

Garth Tander

Holden Commodore VF

01:03.22

00:00.94

14

Erebus Motorsport V8

Ashley Walsh

Mercedes E63 AMG

01:03.27

00:00.99

15

Supercheap Auto Racing

Tim Slade

Holden Commodore VF

01:03.28

00:01.00

16

GB Galvanizing Racing

D.Wood/M.Jones

Holden Commodore VF

01:03.39

00:01.11

17

Nissan Mororsport

James Moffat

Nissan Altima

01:03.47

00:01.19

18

DJR Team Penske

Scott Pye

Ford Falcon FG/X

01:03.47

00:01.20

19

Super Black Racing

Andre Heimgartner

Ford Falcon FG/X

01:03.49

00:01.21

20

Walkinshaw Racing

Lee Holdsworth

Holden Commodore VF

01:03.51

00:01.23

21

Wilson Security Racing GRM

David Wall

Volvo S60

01:03.54

00:01.26

22

Nissan Motorsport

Michael Caruso

Nissan Altima

01:03.68

00:01.40

23

Repair Management Aust Racing

Nick Percat

Holden Commodore VF

01:03.88

00:01.60

24

Holden Racing Team

James Courtney

Holden Commodore VF

01:03.91

00:01.63

25

Nissan Motorsport

Todd Kelly

Nissan Altima

01:04.76

00:02.49