Race leader Glenn Smith spent the closing laps of Saturday’s Taupo 3-Hour endurance watching a low voltage alarm repeatedly appear on the dash.
The problem had already required an unscheduled pit stop with about 35mins remaining to fit a new battery to the Holden Commodore, which Smith had taken over from car-owner John De Veth with just before the two-hour mark in the opening round of the Mahindra North Island Endurance Series.
The extra stop sacrificed one of the four laps of margin they held over the Chevrolet Camaro GT3 of Inky Tulloch and John McIntyre that was recovering fast from a mid-race delay.
‘‘The engine cut out on the main straight which was lucky because I was able to coast straight into the pits,’’ said Smith.
De Veth had driven for nearly the two-hour maximum at the start of the race, building a lead that positioned the team to achieve their second win as a driving duo following a Hampton Downs 3-Hour victory last year.
The 7.0-litre Commodore is the original prototype for the V8 SuperTourers category — with some endurance racing modifications.
The Tulloch/McIntyre Camaro had set the pace in qualifying and posted the fastest lap of the race but from early on was trailing smoke and not running at full pace.
Tulloch started the car and was initially down in eighth place and had advanced into fourth spot when he stopped to hand over to McIntyre.
When the car pitted it was found the source of the smoke it was trailing was hot engine oil being pumped into the gearbox and then escaping via a breather.
McIntyre drove the rest of the race and had reached second place just before Smith coasted to the pits for the rapid battery change. His pace closed the gap to a lap-and-a-half at the finish.
The issue with the 7.9-litre Camaro was in a heat exchanger that should separately cool the engine and gearbox oil. But a failure in that component was allowing hot engine oil to mix with the gearbox oil.
‘‘There was so much oil pressure in the gearbox that it was difficult to downshift,’’ said McIntyre, who charged hard through a near two-hour stint that was his first competitive drive since the Bathurst 12-Hour in February.
‘‘The crew did a fantastic job working out what was causing the problem and the main thing is we got the car home to a good finish and some good points in the series.’’
Third place went to the consistently driven Ford Mustang Boss 302S of Bernard Verryt and Aaron Harris which was easily the best of production-based cars. The challenge of the European sports cars in the GT Class faltered.
The Trass Family Motorsport Ferrari 430 GT3 had qualified second fastest and Jono Lester took the race lead at the end of an opening lap which had seen the grid order mixed up by a Le Mans start format.
Lester was building a comfortable lead when the Ferrari was halted about the 30-minute mark with an engine problem.
Two Porsche 911 GT3 cars were also contenders and when De Veth made a fuel stop during the only safety car period of the race near the one-hour mark, the Porsches led the race.
The Sam Fillmore/Andrew Porter and Rhys Warren/Rick Armstrong cars ran close together for the first hour but soon after the safety car Warren was halted on circuit when the engine cut-out.
The Fillmore/Porter Porsche was having clutch problems and was unable to leave the pits after its mid-race stop because the clutch failed completely.
Behind the Class 1 (over 3500cc) winning Verryt/Harris Mustang the top five was completed by the Ford Falcons of David and Matt Dovey and Bruce Kett/Shane Johnston.
The eighth placed Richard Bilington/Lewis Scott SEAT Leon SupaCopa claimed the Class 2 (2001-3500cc) honours and the Honda S2000 of Hayden Johnston/Damon Jackson was ninth and won Class 3 (1601-2000cc).
The sole Class 4 (0-1600cc) entry of Richard Gee/Shaun Morris (Honda Civic) climbed into the top-10 before slipping to 11th with a late race fuel stop.
The earlier 1-Hour event had its start delayed by fog shrouding the circuit. Ian Hayr in his Porsche GT3 Cup car qualified on pole position and led from the start in his Porsche GT3, only relinquishing the lead briefly mid-race after making his compulsory pit stop.
Sixty minutes later Hayr was almost a full lap clear of the Holden Commodore SuperTourer of Simon McLennan that moved through the field from 20th place at the start.
The top-five was completed by a trio of cars one lap down on the leaders – the Ford GT40 of Deon Cooper, the Fillmore/Porter Porsche and the Ford Mustang Boss 302S of Rick Cooper.
The next round of the Mahindra North Island Endurance Series is at Hampton Downs on June 27.