
Holden driver Mark Porter was hit directly by Ford driver David Clark at the top of the circuit during the Fujitsu series race.
Ambulance crews freed both men and rushed them to nearby Bathurst Hospital, where Porter is said to be in a critical condition.
He had spun sideways after clipping a wall near the esses.
His Commodore was left stranded in the middle of the track in an area blinded to oncoming traffic.
One V8 racer managed to avoid the stricken Porter but Clark could not steer his Falcon out of the way and smashed directly into the driver's side door.
The accident occured on the 12th of 14 laps.
The main race for the weekend, the Bathurst 1000, has been placed on hold with its qualifying session expected to have started at 1400 AEST.
Porter was also scheduled to partner Dale Brede in Sunday's Bathurst 1000, driving for Team BOC Falcon
Source: AAP 2006