There's a 1903 Cadillac in the shed, too, which gives less trouble as the Americans standardised production earlier than the quirky Europeans - each of Barry's apparently identical de Dion motors has a different-sized piston.
I would love a closer look at the 1907 International Buggy, it's only had two owners - Barry bought it in 1977 and corresponded with its original caretaker, amassing quite a bit of material on the car. "They touched up the paint in 1951," he says, pointing out the bits that aren't original. It's not running today, "It's not too reliable, I don't think it was
a good car originally," though it was good enough to cart coal into the 1950s after a newer vehicle replaced it in 1915.
I get distracted by old photos of it in action, before wrenching Barry's attention to the one I'm here to see - the first car to get electric start as standard. This 1911 Cadillac 30 cost £585 when sold new to the Mayor of Otaki by Dexter and Crozier. That was equivalent to a house in Auckland's upmarket Remuera at the time, and double a Model T Ford. Cycling was big business in the late 1800s, some companies made a packet, then smelled the winds of change and shifted to cars, Dexter being one.
This Caddy has electric lights as well, and was originally sold with five glass batteries - four in series making 24 volts - all mounted in a box on the left-hand running board.
Modern batteries are bigger, and Barry's had to reroute a few things. The car starts on six-volt, switches to 24 when in mesh with the flywheel then back to six. What electric start meant in practice was that women, who often couldn't manage a big-engine's crank handle, could now drive.
He pours petrol into the priming taps - it's a cold day or he wouldn't need to - then tries the starter, but it fails to fire and he resorts to the crank, and the engine turns over with a wheezy cough. But it won't idle, then is reluctant to restart, a rare occurrence Barry blames on the presence of me and my notebook. And camera ...
"That's not normal, it's very reliable, but ... " The most likely answer is old fuel - unleaded deteriorates fast and these old cars are fussy, especially at the end of winter, when they've rarely been run.
Eventually he gets it into a chuntering idle, the roof straps wiggling and the mudguards jiggling and we clamber aboard - both through the passenger door as there isn't one on the driver side, and we're off, though it dies on us twice on the way home. Turns out it's not old fuel, or engine wibbles - he forgot to top up the petrol!
Barry Birchall's 1911 Caddy's a bit bouncy and draughty even with the roof. Pictures / Jacqui Madelin
That sorted, he roll-starts it (backwards) and off we go again.
The car's got a four-cylinder 4-litre engine and three-speed gearbox, with a pair of big drum brakes, on the back axle only. The clutch is hellish jerky, it was smoother when it had leather on it Barry says, but it didn't last so he fitted modern materials. It would be quieter with the roof down but I can hear his guided tour of the switches and gauges, the oil one the most important as this is a total-loss system, oil goes into a big tank up front, drips down through the engine and out on to the road ... I must say she's a bit bouncy, there's not much shelter even with the roof, and I admire Barry and his wife for driving it to Napier - it took eight hours, cruising at 80km/h (it tops out at 100), though he might not do it again as the Napier-Taupo road's a bit steep.
The first Thames fire engine was built on a 1912 chassis, some towns lengthened the body and fitted extra seats to carry passengers, and Newmans and the Hawkes Bay Motor Company bought these cars to replace the stagecoach in 1912. Napier looks like a marathon from here, but Barry's driven the 1903 Caddy to Christchurch, cruising at 40 to 50km/h and hugging the verge.
He likes the social aspect of car clubs and the convenience of the internet - on which he orders these 27-inch tyres from the US at $1000 a pop! Good thing they last, "As you are not doing a lot of miles," he says, and "if you have good tyres and the engine is in good condition you can run an old car on very little."
• The Horseless Carriage Club will have a display on Wynyard Wharf from about 11.30am on October 12, and a rally will start at Ambury Regional Park, Mangere Bridge, at 9am on October 26.