Greg Murphy's Holden Barina AP rally car will get its first taste of gravel at this week's West Coast Rally.

The former Supercars star launched the new Barina a month ago at Hampton Downs but will hand the keys to teammate Josh Marston for the weekend's gravel debut.

Murphy, a four-time Bathurst winner, is unable to compete due to a clash with the Supercars season-opening event in Adelaide so Marston will put the car through its paces.

"That is a really important next phase testing the car," Murphy told "Josh will be able to get a good feel for it and see where it is at from his feel.


"That is going to be its first foray getting it dirty and giving it some gravel rash."

Murphy as had one competitive outing in the car however having competed on Rod Millen's driveway at Hahei.

"We did the Leadfoot Festival which was really good for us after the launch," Murphy said.

"To do a bit of competition even though it was on tarmac - the loads that are generated on tarmac do force things to be tested and we didn't really have any issues with drive line or the drivability of the car.

"We highlighted a couple of issues with electronic things which we have managed to get on top of."

The build of a second Barina will be completed shortly, which Marston will use in this year's New Zealand Rally Championship.