They had driven themselves into third place when the fuel pump on their Porsche 996 GT3 Cup car began intermittently failing.
"So much for the car being reliable," Dippie said, with a laugh.
They ended up 15sec behind Brent Esler and Andy Neale, of Christchurch, in a BMW M3 GTR.
"We were still happy with fourth. The car could have stopped and not finished," Dippie said.
The problem will have been fixed by tomorrow's second round at Christchurch's Ruapuna Raceway, where the Dippie-Aitken pairing are hoping for a podium finish aided by the knowledge second-placed team Scott O'Donnel, of Invercargill, and Simon McLennan, of llington, are not competing.
Canterbury Porsche 997 GT3 drivers Paul Kelly and Kevin Bell took victory in the opening round, 53.648sec ahead of O'Donnell and McLennan in a similar Porsche. The two cars had been involved in a fascinating battle as their fortunes ebbed and flowed over the three hours.
Alexandra duo Bruce Davidson and David Garden were sixth in a Chev Corvette.
Retirements from the race included Arron Black and Warren Good, of Dunedin, in a BMW E46. Good swerved to miss a car slowing for a yellow flag and made heavy contact with the wall, ripping the right front tyre off and damaging the suspension.
Black said it was a shame as they had qualified fourth-fastest but he hoped the car would be fixed in time for tomorrow.
His brother, Stuart Black, also of Dunedin, had earlier won the one-hour race in his Toyota Starlet.
Nelson's Dougall MacGibbon was the fastest qualifier in the same car make and model but Black reeled him in early on and took the lead. The duo ran at the head of the field until MacGibbon was sidelined by a blown diff.
Black let Grant Molloy in a Mitsubishi Mirage carve into his lead over the final laps but he crossed the line 2.241sec ahead of the Invercargill driver.
Black's race was characterised by some brave passing moves around the outside of the loop.
Jamie and Lee Hodgins, of Dunedin, in another Toyota Starlet finished third, the only other car to complete 44 laps.
After today's second round, the series will have its finale at Levels Raceway in Timaru on October 15.
