Craig Lowndes will need to unleash his inner mongrel if he wants to beat Holden teammate Jamie Whincup to this year’s V8 Supercars title, Ford rival Mark Winterbottom says.

Grid favourite Lowndes is just 20 points shy of series leader Whincup as he hunts down his first championship since 1999 at this weekend’s season finale at Sydney Olympic Park.

Despite the looming battle, the Red Bull duo insist their friendship is tighter than ever.

But Winterbottom, 124 points behind Lowndes and out to spoil the pair’s party, predicts the pleasantries will be short-lived.

“At the moment they’re pretty chummy and stuff, but there’s a point where it’s going to have to change,” he told AAP.

“They’ve let it drag on for a while without really going hard at each other.

“I’ll be putting the pressure on them. They’re going to finish to win – and if one doesn’t finish, the other bloke’s going to win.”

Winterbottom said Saturday and Sunday’s 250km races provided Lowndes the perfect opportunity to step out from four-time champion Whincup’s shadow and stamp his claim for a fourth title.

“He’s watched Whincup win the previous four (of five) championships,” Winterbottom said.

“He gets equal equipment and the same opportunity, so there’s a point where you’d get pissed with your teammate getting all the results on the track.

“So there has to be a point where he’d have to find that mongrel to beat him. He’s going to have to – because if he just keeps driving like he is, Whincup’s going to win it.

“He has to dig deep and get a bit aggressive and race his teammate and show him that he wants it.”

Lowndes has a proven record at the Sydney 500, winning two of the last four races.

Whincup, however, has never finished on the podium nor scored pole position in the event’s eight-race history. His best finish is fifth place (four times).

It’s the only circuit on this year’s calendar that Whincup has not won a race at during his V8s career.

Meanwhile V8 Supercars has ordered all drivers to make at least two pitstops in each leg of the Sydney 500 as part of its continued bid to help alleviate the disadvantage of higher fuel consumption for newcomers Nissan and Mercedes.

Similar measures were enforced at this year’s Sandown and Bathurst endurance races.