The top five cars were determined by public vote and each owner was given a trophy. There were also prizes for the sponsors' choice and the mayor's choice.
Mr Saunders hoped to hold the event annually, with proceeds going to a different charity each year.
"I'd like to do Organ Donation NZ every two or three years but there are also a lot of charities out there who are under promoted. While I'm breathing, I'll be trying to do something for them."
Organ Donation NZ spokesperson Melanie Stevenson said the 150 cars involved attracted large crowds to The Strand.
Eighteen girls from all over the North Island entered the pin-up competition, won by Rotorua's Monique McLennan, 24.
"The whole point of the event was to raise awareness for organ donation and encourage people to talk about their wishes to their families. I loved it, it was great to see the pin-up ladies, they were beautiful. It was amazing that Trelise Cooper came down and supported the day."
A lot of people had been interested in the Organ Donation NZ stall, Ms Stevenson said.
"We gave away more than 200 T-shirts and talked to a lot of people about organ donation."