Scott McLaughlin sounds Supercars title warning

Scott McLaughlin drives the #17 Shell V-Power Racing Team Ford Falcon FGX during the Newcastle 500. Photo by Daniel Kalisz/Getty Images

Ford star Scott McLaughlin has laid down the gauntlet to Supercars championship leader Jamie Whincup with a blistering practice lap in Newcastle.

McLaughlin posted the fastest lap around the street circuit, which is being used for the first time, in one minute and 9.5949 seconds on Friday.

The 24-year-old Kiwi's performance sounded an ominous warning to Whincup, whom he trails by 30 points in the title race as the season-deciding meet got underway.

McLaughlin put a 0.4345-second gap between him and Whincup, the second-fastest for the day.

The DJR Team Penske ace said engineer Ludo Lacroix had tuned the car to perfection for the second session.

"To be the fastest by a margin is nice but we've got a long way to go and we'll focus on it overnight," McLaughlin said.

"I've got a few things I need to work on myself - the lap wasn't completely perfect.

"Ludo and myself will knuckle down and try and make the car even better."

Two second-placed finishes will be enough for Whincup to clinch an unprecedented seventh championship, even if McLaughlin can manage a clean sweep.

But both leading title contenders are cautious of declaring the weekend's two 95-lap races as two-car contests.

"There's 24 other guys and girls out there trying to get in front," Whincup said.

"We won't have it all our own way. Hopefully it's a good, fair race, both cars are reliable and we go there and race hard."

Nissan driver Todd Kelly's final race weekend as a full-time driver got off to a flyer as he posted the third-fastest lap of the day.

Whincup said the circuit was "heart in mouth" after recording the quickest time in the first session.

"It's going to be a crazy challenge to get it all right and keep it clean for 95 (laps) times two this weekend but that's all part of the job," Whincup said.

"I thought there would be a bit more flow but it's actually quite stop-start. The grip is slightly higher than anticipated and it's bumpier than we anticipated."

Qualifying for Saturday's 250km race, the first of two for the weekend, starts at 11am AEDT.