At Australia's biggest and most prestigious modified car show where so many different styles of vehicles compete for the judges' points, less than a handful of hot rods have won in 32 years.

"I'm speechless; it's just the weirdest feeling, completely surreal," said the Gold Coast-based fitter and turner, who built the hot rod, called Tequila Sunset, in his garage at home, based off sketches made by his daughter, Danielle.

The father and daughter shared in the prize although the cramped little cabin of the tiny custom-built pick-up truck was barely big enough to accommodate the Summernats champion's traditional broadsword.

Danielle said she was very proud of her father and his effort put into building the car. It took six years to create, the results of hour upon hour of hand-crafting components and turning out custom parts on a lathe.

The grand champion's sword is regarded the most difficult prize to win at Summernats because the successful vehicle not only must be an elite show car but the owner must also compete in track events like the slalom and the go-whoa acceleration test to prove the vehicle's engineering integrity.

Many elite category entrants can't stomach the idea of taking their pride and joy out of a protective environment but since Rick drives his award-winning hot rod on the public road quite regularly, the Summernats track competition was not a problem.

"I've driven 6000 kms on the road around the Gold Coast in this car since I brought it here for the first time last year and made it into the top 10 elite," he said.

"I guess that's why I really didn't think we'd have much of a chance this year because it's really hard to compete against high-end show cars that are flawless, brand new builds."

To compensate, he spent three solid weeks detailing every square centimetre of Tequila Sunset's candy apple paintwork, undercarriage and supercharged V8 engine.

The winning car was produced from a mould taken from a 1932 Ford pick-up truck.

"But it's nothing like the original because it's been so chopped and changed around," Rick said.

"The back tray was all hand-made at home, as is the grille shell, the chassis and the exhaust.

"Danni and I wanted our own Hot Wheels car so she came up with some ideas and I took it from there."

As smoke and water don't mix, the heavy thunderstorms which swept across Canberra late on Saturday afternoon played havoc with the qualifying for the burnout competition. Organisers rushed the competition forward before the rain came and washed out events for a few hours.

However, Sunday's finals and burnout masters competition went ahead as scheduled, attracting the usual huge, enthusiastic crowds.

Crowds for this year's four-day event reached more than 107,000, with entrant numbers strong at over 2199 cars.

The ACT Environmental Protection Agency reported five complaints over the Summernats weekend; one about noise and four about smoke and odour, all during burnouts.

Event organisers said that "one or two people" had received treatment for heat stress-related illness on Saturday. ACT Policing said they had no callouts to Summernats on Sunday.