Qualifying format explained

One session, two races, 50 drivers - here's how Saturday will play out at the Wilson Security Sandown 500.

The drivers will have one last chance to tune their cars ahead of qualifying during Practice 4 this morning. The 40-minute session is open to all drivers and will kick off at 10.20am.

Then, a standard qualifying session will run at 12.20pm. This 20-minute hit-out is open to both the primary driver and co-driver, and will determine the grid for qualifying race one at 2.00pm.

The first qualifying race will see the co-drivers pitted against each other in an andrenalin-charged 20-lapper around the 3.1km Sandown circuit.

Where they finish will be where the main drivers start when they jump in the cars for an all out dash for ARMOR ALL Pole Position at 4.10pm.

No Championship points are on offer today, so the drivers will be putting it all on the line for that front row start in the 500.

With Prodrive Racing Australia's Chaz Mostert currently the pole king this season - with 10 poles to his name - will the young gun be able to claim his place in the number one grid spot with today's unique qualifying format?

Will Jamie Whincup be able to break through for AMOR ALL Pole Position after being quickest overall in yesterday's practice sessions?

Stay tuned to see where your favourite driver will start tomorrow's 500 kilometre haul at the Wilson Security Sandown 500.