Wood will join Zach Bates as part of WAU's re-entry into Super2, the team's first foray into the second Supercars tier since 2012.
The WAU deal follows a successful 2022 season for the 19-year-old, who won the Porsche Sprint Challenge title with six poles and four round wins from the six events.
He was also crowned the South Island Endurance Challenge champion in his native New Zealand.
Wood had been set to join Earl Bamber Motorsport for Carrera Cup this year as part of the Porsche New Zealand programme.
However, following a recent driver evaluation day with WAU, that plan has been shelved so Wood can join the Supercars system.
“There’s no doubt it was a really tough decision to make the switch from Porsche New Zealand and Earl Bamber Motorsport, they’ve been amazing for me, and I can’t thank them enough for all that they’ve done,” said Wood.
“It’s been a dream of mine since I was a kid to race Supercars, so I’m really excited to chase that dream with Walkinshaw Andretti United and see what we can do together next year.
“It’s going to be a big learning curve, but the team have already been amazing so far, so I can’t wait to get stuck into the season.”
WAU boss Bruce Stewart said the team was impressed from what it saw from Wood at the Winton test last month.
“We have been following Ryan’s career closely for a while now and got the opportunity to see first-hand his talent at our recent driver evaluation day, where he more than impressed everyone there,” said Stewart.
“It wasn’t just the way he drove, but the way he interacts with the team around him. We think he’s a great fit for our culture here at WAU, which is really important to us.
“We think Ryan’s got a very bright future ahead of him, and are looking forward to seeing him alongside Zach, who we think we work really well together on and off the track.”
The 2023 Super2 season kicks off in Newcastle next March.
