DJR Team Penske’s true form at Symmons Plains remains unclear after a late set-up change prevented Fabian Coulthard from completing a green tyre run in practice.

Coulthard ended up just 23rd on the time sheets after falling marginally short of starting his flying lap before the chequered flag fell in Practice 2.

The #12 Ford had been garage bound for most of the final quarter of an hour while the team attempted a front-end set-up change.

Coulthard had spent the earlier part of the session chasing speed on pre-marked soft tyres at a circuit where the then single-car squad struggled last season.

Although scoring two poles in Adelaide and a podium at Albert Park, the expanded team has been cautious about its chances upon returning to the tight Symmons layout.

Coulthard’s team-mate Scott Pye was eighth fastest after his green tyre run in Practice 2, just 0.2s from pace-setter Mark Winterbottom.

The front-running was dominated by fellow heavy-hitters Prodrive and Triple Eight, which together locked out the top five spots.

“Deciding to make a change very late in Practice 2 did not allow us the time to get on track and really have a crack with the new tyre,” confirmed Coulthard.

“We are still trying to improve the Detroit Ford every time we go out.

“Thankfully Scott got a good lap in so we have some data to look at from both cars, but I would have liked to compare apples with apples as we get ready for qualifying on Saturday.”

Pye had spent almost the entire day on pre-marked hard tyres before a brief spell on a used set of softs to prepare for his new tyre run.

The bulk of the field spent the majority of the day using pre-marked softs from their bank ahead of a race meeting that will see both qualifying sessions and races run on the soft rubber.

“The car was pretty good,” said Pye.

“We improved it during the day on the hard tyre, while the bulk of the field were on the soft option.

“I think it is a strategy that will repay us in later rounds.

“We kept a level head as we knew what the program would be with the Western Star Ford.

“I moved onto the Soft tyre at the end and we bounced up in 8th place.

“I felt we could have been a bit more aggressive but to be in the top 10 today was a good result.”

Although a final 15 minute practice will take pace tomorrow morning, the new set allocated for each car today may not be used.

That rubber is instead added to the pre-marked bank to be used at subsequent meetings.