John Zappia has returned to the lead of the 2017/18 400 Thunder Pro Slammer Championship with victory at the penultimate round of the series in Sydney.

Top Fuel pilot Peter Xiberras had his challenge for the 400 Thunder Top Fuel Title well and truly underway at Gulf Western Oil Nitro Thunder on the weekend, reducing the gap between he and title leader Damien Harris with a round one victory, before a round two incident saw Xiberras hit the wall in his PremiAir Racing dragster.