Nick Cassidy has finished two days of testing for the SUPER GT series as the fastest driver in Japan's equivalent of V8 supercars, in his Lexus LC 500.
With co-driver Ryo Hirakawa the pair dominated, setting the fastest times on both days, bettering the efforts of former Formula One drivers Heikki Kovalainen and Kazuki Nakajima.
Testing was held at the Okayama track, where the first round of the series will take place in three weeks time, with just eight tenths of a second separating the top ten cars. Cassidy's best lap was 1 minute 18.395 seconds.
"It was a really promising test for us," said the Aucklander. "With the LC 500 being new, we are continuously learning and developing the car and selecting the best tyres."
Kovalainen, the defending champion was fifth fastest and Nakajima ninth. Apart from five other Lexus LC 500 teams, there are also factory entries from Nissan and Honda.
Cassidy said it was difficult to assess what the initial success meant. "Every team has their own program in testing, but it's still better to be in this position."
Both Hirakawa and Cassidy completed long runs, simulating the conditions they will meet under racing in the endurance series where events vary between 300 and 1000 kms long.
The former double Toyota Racing Series champion and Hirakawa had to pick their way through the slower GT300 class cars, which were also on the track at the same time.
Their front running GT500 class Lexus develops over 500 horsepower from a two litre turbocharged engine.
They will have another test session at the Fuji circuit before returning to Okayama for the first of the eight rounds in the series.
Cassidy finished fifth in his first season of SUPER GT when he drove a Lexus RC F last year.