Broc Feeney admits his surprise at claiming a victory in Perth after youngster Ryan Wood was cruelly denied back-to-back wins.

Wood endured a roller-coaster ride at Wanneroo Raceway after suffering a suspension failure in the second 120km sprint on Saturday, just hours after his maiden race victory.

Pole-sitter Wood had given up the lead off the starting line to Tickford's Cam Waters, but proved his mettle by valiantly reclaiming top spot on lap 22.

Just as the 21-year-old looked set to cruise to a second victory, he lost control at turn six and ventured into the dirt.

He went straight to pit lane after recovering and finished 24th out of the 25 drivers.

Triple Eight was the beneficiary of Wood's bad luck, with Feeney and reigning champion Will Brown jumping the pack with masterful use of the undercut.

"Probably a little bit surprised to walk away with the win in that one," Feeney said.

"Running around in fourth, you probably didn't expect to play out like that."

Wood's Walkinshaw Andretti United teammate Chaz Mostert was also in disbelief after finishing third.

"Nothing's for certain in this," Mostert said.

"Started in 11th, didn't expect to sit here. Who knows?

"This championship all year has been a little bit unpredictable."

New Zealand product Wood had earlier on Saturday shed tears after crossing the finish line first.

"To achieve my lifelong dream just doesn't feel real," Wood said.

Wood secured the lead on lap 11 out of 50 after almost forcing pole-sitter Mostert off-track with a dive on the inside on the way to turn seven.

He then fought off Feeney after being caught at pit exit with cold tyres, before Brown chased him down across the final 15 laps.

In the end, Wood claimed victory with a 0.612-second margin over Brown.

Mostert crossed the line third, with Feeney fourth.

Wood will have an opportunity to find redemption when qualifying for the final Perth sprint gets under way at 1pm (AEST) on Sunday.

RACE 14 RESULTS:

1. Ryan Wood (Walkinshaw Andretti United)

2. Will Brown (Triple Eight Race Engineering)

3. Chaz Mostert (WAU)

4. Broc Feeney (Triple Eight)

5. Brodie Kostecki (Dick Johnson Racing)

RACE 15 RESULTS:

1. Broc Feeney (Triple Eight)

2. Will Brown (Triple Eight)

3. Chaz Mostert (WAU)

4. Cam Waters (Tickford Racing)

5. Matt Payne (Grove Racing)

CHAMPIONSHIP STANDINGS:

1. Broc Feeney (Triple Eight) 1036 pts

2. Will Brown (Triple Eight) -27

3. Matt Payne (Grove) -107

4. Cam Waters (Tickford) -117

5. Chaz Mostert (WAU) -251