"It's a great way to see some beautiful scenery," member Chris Torr said.
"They're not fast, but you drive carefully, keep your eye on the mirror and let faster traffic pass.
"It's all about the people and the places, and the cars are a common interest. We always have a ball."
Mr Torr, based in Feilding but raised in Kahutara, drives an original two-seater 1937 Morris Seven.
"I came home with it on Christmas Eve, 1991, and my wife says, 'what on earth are you going to do with that?'" he said. "I started restoring it and, almost exactly 20 years later, it was back on the road."
Mr Torr said he enjoys the Morris because the cars are "cute and have a certain style", they don't take up much room, and are easy to repair "without fancy gear". Car parts are also easy to come by -- handy in a breakdown on long trips.
"We go foraging along the way -- it's amazing what you can find," Mr Torr said.
"We had one lady lose her clutch at Blackball on the West Coast, and the guys at the fire station put us on to a man who had all these different Morris parts in his garage. He had just the right one."
Also joining the trek from South Wairarapa were Featherston couple Judy and Neil King, driving their 1974 MGBGT, which they bought "from a guy in Cole St".
The secret to a Morris car performing well is keeping it in tip-top condition.
"You have to watch out for rust -- you absolutely need a carport or garage. You need a good mechanic, and keep up with maintenance."
Mrs King said she loves the "prettiness and elegance" of Morris cars.