The team, known as Revved Up, made it into its third national championship in a row last October, after winning back-to-back titles in the professional class at the state championships in Launceston.

The team already won Australia's fastest car at last year's national championships, in a time of 1.05 seconds over 20 metres.

This year it hopes to reclaim that title as well as be the overall champion and represent Australia at the world titles in Abu Dhabi.

William Ball, Nathan O'Toole and Kaleb Clark have worked together to design and make the new car for the nationals.

William, who is the team's design and manufacturing engineer, said the car was the same one it raced in the state finals but had had a number of changes.

``I've make the car longer so air has more time to adapt to the car,'' William said.

The car is also a tear drop shape, the wheels have been coated in a slippery substance so they slide easier down the track and there is a hole down the middle of the car.

``That came from researching catamarans, which are on the two skis,'' William said.

``One of the aims of designing a car is to get as much air behind the car to act as a wall, so having the hole means air can run straight through the middle.''

The boys will leave on the Spirit of Tasmania tomorrow and begin their four days of intense judging at the Canberra championships on Monday.

Kaleb said  the team's booth displays, designs and posters would also be judged.