"There's a very well and clearly defined line for anyone with a decent amount of commonsense between strong rivalry and banter and bullying and death threats and all of the other stuff we're seeing here," Seamer told the Newcastle Herald in an interview after the first day of practice at the Newcastle 500 on Friday.

"We're working and will be working with the teams to take some of the heat out of it over the next 48 hours so we can finish the season on a high.

"You can bet that we'll be spending some significant time over the off-season around our communications and social media policies."

Asked if he was referring to bullying by drivers, he said: "I mean anyone bullying anybody.

"It's very easy for people, and I'm not pointing fingers at anyone in particular, but it's very easy for people to sit behind a keyboard and throw around loose insults.

"Social media snowballs so quickly nowadays. It's not like 10, 15 years ago.

"The problem is that once people start to jump on the bandwagon things get out of control very, very quickly, and we're dealing with real people with families and wives, and we need to remember that.

"If you wouldn't say something to someone's face, you shouldn't be saying it from behind a keyboard."

McLaughlin, who will claim his second consecutive Supercars crown on Sunday regardless of results in the season-ending races, has attracted claims from rival drivers that his second title is "tainted" or "invalid" since his winning car at Bathurst last month was found to have used an illegal engine in qualifying.

His DJR Team Penske teammate, Fabian Coulthard, reportedly received death threats after slowing down behind the safety car on team orders to give McLaughlin an advantage at a crucial stage in the race.

McLaughlin has countered the critics by arguing that his car has been found to have "one technical infringement in one qualifying out of 325 times being scrutineered".

Commodore driver Scott Pye reignited the controversy on the eve of the Newcastle race weekend when he compared McLaughlin with disgraced American cyclist Armstrong.

"Even if it was once, that's enough to bring everything into question. Lance Armstrong (most tested athlete) was caught once, but it ruined his whole career," Pye wrote on Instagram.

Fellow Commodore driver Nick Percat agreed that Pye had "hit the nail on the head".

Seamer told the Newcastle Herald that Supercars was "reviewing everything and talking to the individuals involved".

Outspoken Erebus Motorsport driver Dave Reynolds has been one of McLaughlin's fiercest critics, and veteran Mark Winterbottom said in Newcastle on Thursday that the Kiwi's title was "tarnished".

But Cameron Mason, who finished second in Friday's second practice session, defended his fellow Mustang driver.

"Everything that's happened is not Scotty's fault. He's had nothing to do with any of that," Mason said in the post-session media conference.

"It's happened. Move on.

"It's a bit poor when those guys say that kind of s---.

"I love banter, but that's s---. There's no more to that. It shouldn't be said."

Some of the frustrations have stemmed from the perceived advantage Ford's new Mustangs have had over the rest of the field this season, something Supercars tried to address after 10 races this year by changing the car's aerodynamics.

Some of McLaughlin's rivals also believe he should have been disqualified at Bathurst.

The 26-year-old has racked up more wins, 18, than any other driver in an Australian touring car championship, and leads the series by an unassailable 550 points before tomorrow's first 250km race in Newcastle.

Asked if the perceived light penalties had fuelled what McLaughlin has labelled a "toxic" atmosphere among drivers, Seamer said: "I think there's a sense of frustration from the pit lane that this is a year that's been dominated by technicalities, technical infringements, rule books and fines, and what we want to do is focus on putting on the best possible entertainment and show.

"Some of that frustration's boiling over, but there's no excuse for it.

"We're all professionals here. We all need to get back to what we're being paid to do."

He said Supercars would avoid having "ongoing changes like we did this year" in 2020.

"We certainly don't want a repeat of this year; I can tell you that much."

On the track, seven-time champion Jamie Whincup struck a blow for the Triple Eight team in the race for the teams championship when he led the time sheets on day one.

Whincup lapped in one minute 10.3173 seconds in his Commodore to edge out Waters' Tickford Engineering Mustang by 0.0057 seconds.

Kiwi Shane van Gisbergen was third in the other Triple Eight car, boosting the team's hopes of making up the 116 points on Penske in the battle for the teams crown.

McLaughlin was fourth, less than a tenth of a second behind Whincup, and Coulthard was eighth.

McLaughlin had set the pace in the first practice session with a time of 1:10.6092.

Whincup came within a whisker of McLaughlin's lap record of 1:10.3057, set last year, even though changes to the turn 11 hairpin have made the track slightly longer and, in theory, slower.

Whincup, who snatched the title in dramatic circumstances by winning the Sunday race in Newcastle in 2017, said after practice on Friday that forecast rain this weekend could make the track treacherous.

"We did the track walk, and there's a lot of white lines that are now painted black, but I think they're going to be just as slippery as the white ones would have been," he said.

"So a lot of paint out there, so it's going to be a gnarly place in the wet."

Whincup said he was a "little bit torn on the weather" because of the state's bushfires.

"Of course, we don't want it to rain for racing, but, man, the community needs some rain around here to put out bushfires.

"Hopefully it buckets down Saturday night and dries out for the race."

Asked about newly laid bitumen on the track from Shortland Esplanade to the Nobbys hairpin, Whincup said it was "proven race mix" and "good stuff".

Supercars has remodelled the hairpin this year to try to boost overtaking on a tight street circuit which has a tendency to turn racing into a procession.

"There's extra length from the kink to the hairpin. That's a plus," Whincup said.

"The corner's actually a lot slower now because the radius is tighter. Those two things combined could open up an opportunity.

"It's still a bit of a desperado to fly down the inside there, but there's plenty of them out there."

He said the Triple Eight team had worked hard to stay in contact with Penske for the teams championship since Mustang drivers won nine of the first 10 races.

"If you'd said we'd be in contention after the grand prix this year, it's absolutely no chance.

"Full credit to everyone: we've ground it out bloody hard to give ourselves at least a shot."

A steady stream of people came through the gates on day one, including thousands of school children, as a cool southerly cut the 33-degree morning temperature by more than 10 degrees in the afternoon.

A damp mist also settled over the city by lunchtime.

Merewether first-time driver Cody McKay provided the first big accident of the day when he ploughed his Aussie Racing Cars vehicle into the wall in Zaara Street.

The 31-year-old walked away from the bingle, but his team face an uphill battle to repair the car before Saturday's racing.