Mark Winterbottom has bounced back from a troublesome first day at the Sydney 500 with a blistering practice run before qualifying on Saturday.

Ford’s championship leader topped the timesheets with a lap of one minute 27.7117secs in the final warm-up session, ahead of Nissan’s Rick Kelly and Shane van Gisbergen’s Holden.

Winterbottom holds a 179-point lead over Holden rival Craig Lowndes, who was 15th fastest and almost a second off the lead pace.

The man known as `Frosty’ needs to finished 14th or better in each race to secure the 2015 title – his first ever since his debut in 2003.

Lowndes, meanwhile, is chasing his fourth championship but first since 1999.

The session was stopped twice, with the Holdens of Tim Blanchard and Jason Bright both finding the tyre barriers at turn eight of the tight street circuit.

Qualifying begins at 11.35am (AEDT).