Since its inception the event has raised more than AUS $6.1 million for, making the rally the largest independent fundraiser for the Australian Cancer Council.
Mr Freeman said now at least 200 cars took part each year.
"I wanted to do something a bit more unique and more based around a challenge as well as humour. There's not a lot of things based around humour for cancer."
He said teams in the New Zealand event could choose to donate to the Australian Cancer Council or the New Zealand Cancer Society, as there were quite a few teams from Australia.
He said the NZ Shitbox Rally had raised $370,000 with one team raising $29,000.
Like its Australian counterpart, Shitbox Rally NZ is not a race, but rather a challenge to achieve the unthinkable: to drive cars worth less than $1700 including registration, warrant of fitness and insurance through sprawling farmlands, geothermal wonders, ancient redwood forests, glacial valleys, impeding mountains and cosmopolitan cities.
Organisers source all of the vehicles on behalf of the teams, who bid on them the day before the rally starts.
Among the teams were Kiwi team the Oxford Pie Tarts.
They were sponsored by Hamilton's Oxford Pies, where team member Fiona Barnett works.
"I'm doing it because my brother has done it twice over in Australia and my dad passed away last year and it made me realise how short life is and that we need to get out there and just do it," she said.
Other Oxford Pie Tart member Angela Chase, from Taupo, said she was doing it because her mum died of cancer so she thought it was a good cause.
The Mayhem Maidens, Huihana Kindberg and Kim Gorden, both from New Zealand, said they were doing it because it was an amazing cause and they got the bonus of being able to see the country.
For more information go to www.shitboxrally.co.nz.