Father-and-daughter team Colin and Amy Theodore have already attracted plenty of attention with their iconic design, dubbed Big Crash Opera.

While the public has been wowed by the 3-metre long chassis, race officials were initially nervous.

"Turns out, because we are using the design of the Opera House, the people at Red Bull had to chat with people on the Opera House board to make sure it was OK that we used the design," Amy said.

Colin will pilot the steel-cardboard-and-papier mache vehicle, with Amy his co-pilot perched at the back.

It's not the first time the pair has teamed up for adventure.

"We've done a fair few things together, particularly sports related, including marathons, bike rides and cross-country running," Amy said.

"We're not afraid to do things that seem a little bit crazy."

Being a Red Bull event, you can count on this billy cart race being extreme.

Video of races in the series feature plenty of crashes and billy carts disintegrating on impact.

But the Theodores insist theirs is not a kamikaze mission.

"Our aim is to make it down the track in one piece, or at the very least finish the race," Amy said.

"We've seen video after video of people crashing, but we've been 'studying' them and thinking about how to tackle each of the obstacles."

The 50 billy carts chosen to contest the event, in Centennial Park, will be judged in three categories: how fast they complete the 500m track, showmanship, and creativity.

Colin said their billy cart had exceeded all expectations.

"Initially we were just looking to create a cart that was recognisable as the Opera House, with some inclusions that made it look a bit like a race car," he said.

"But to our surprise, and despite its ultra low-tech, old-school design, it actually gets going much faster than we could ever have imagined."