Scott McLaughlin admits that the reliability of Volvo Polestar Racing’s package remains a major unknown ahead of Sunday’s Supercheap Auto Bathurst 1000.

The #33 McLaughlin/Alex Premat S60 has proven a front-runner all weekend and will start the race from third on the grid.

The team flew in two brand new engines from Polestar’s Swedish headquarters for the event and is the only team to have undertaken planned engine changes during the weekend.

While Friday night engine changes used to be common place, modern reliability sees teams run a single unit across the four days, allowing them ample time for fine-tuning.

A desire to keep miles off its new race units saw McLaughlin’s engine put in on Friday night ahead of today’s final practice and Top 10 Shootout.

The sister entry of Robert Dahlgren/Greg Ritter had its scheduled engine change moved ahead to Thursday after its high-mileage practice motor failed in the early afternoon.

Along with the new engines, Polestar dispatched its engine department chief Mattias Evensson to Bathurst; his first appearance at a V8 Supercars event since April.

“It’s stepping into the unknown, we don’t know,” said McLaughlin of his car’s reliability over 1000km.

“The car has been faultless all weekend. The boys have checked everything and it seems really good.

“I’m driving it hard, I’m not trying to look after anything.

“At the end of the day we’ve just got to keep driving and if something breaks, something breaks.

“The 500kms at Sandown were pretty good but you just never know around here.”

While a faulty sensor also hurt Dahlgren’s practice this morning, McLaughlin and Premat have enjoyed a strong build-up, leaving the 21-year-old optimistic for the race.

“I think we are sneaking under the radar a bit,” he said.

“The car has been feeling fantastic and I’m just looking forward to getting on with it.

“The track does make the car twitchy and the rear-end does step out a lot more because you are carrying more speed.

“(But) our car has been pretty good straight out of the truck so its a testament to the team.

“A podium at least is a chance,” he added.

“That is what we want but really we want the win, so I’m just going to have to drive the wheels of the thing. “