Chaz Mostert posted a new Townsville practice benchmark to edge Scott McLaughlin in a hotly contested second practice.

The Prodrive Racing Australia pilot blitzed the Reid Park circuit in the final minutes as he posted a 1:12.26s to top the times in Friday’s second 40-minute session.

“The car’s obviously night and day better than it was at Darwin and it’s a credit to the guys for going through the data after Darwin and try to assess the mistakes we kind of made, the last round or two,” said Mostert.

“The car felt pretty good, I think there’s a bit more in it if we can just tidy up a few things but a big relief after Darwin.”

Mostert’s time emerged from a frantic final six minutes following a brief stoppage when Erebus Motorsport’s Dale Wood ran on at Turn 2, which prompted the red flags.

The halt effectively provided a qualifying run for the field in the remainder of the session.

Mark Winterbottom topped the times prior to the red flags but he was left to settle for fourth come the chequered flag.

DJR Team Penske’s McLaughlin was the first to strike when the action resumed as he moved to the top, only to be edged by Mostert by 0.16s.

Red Bull’s Shane van Gisbergen briefly held second before dropping a spot to third as he appeared to be enjoying a much better balance with his #97 Commodore.

He did however suffer a spin at the exit of Turn 8 and was lucky to avoid the barriers.

“After Darwin we had a pretty big go through of what we thought was wrong and we fixed it,” said van Gisbergen.

“Straight away the car was much better than the problems I had there.

“(We) worked through a normal program and I think we made some good gains.

“In the race runs we’re a little bit off but we still feel pretty good.

“The car was quite good and I enjoyed it.”

Van Gisbergen’s team-mate Jamie Whincup ended in fifth ahead of Practice 1 pacesetter David Reynolds in the Erebus Motorsport Holden.

Lee Holdsworth showed impressive pace in seventh while Rick Kelly (Nissan Motorsport), Will Davison (Tekno Autosports) and James Courtney (Mobil 1 HSV Racing) rounded out the top 10.

Garth Tander (Garry Rogers Motorsport) narrowly missed out on the top 10 in front of Tim Slade (Brad Jones Racing), Nick Percat (Brad Jones Racing) and Jason Bright (Prodrive) as 0.59s covered the top 14.

Championship leader Fabian Coulthard was only able to manage 18th in the #12 DJRTP Falcon, while Craig Lowndes was 21st after suffering another wild spin at Turn 6.

The Supercars field will return to the track on Saturday for a 20 minute qualifying session at 1230 before a 200km race at 1610 local time.

Results: Virgin Australia Supercars Championship: Watpac Townsville 400: Practice 2