The #17 Keihin Honda NSX-GT of Koudai Tsukakoshi and Takashi Kogure wrapped up the Autobacs Super GT Series’ second and final day of pre-season testing with the fastest time on Sunday, leading a Honda 1-2 at the top of the GT500 leaderboards.
Conditions were similar to Saturday, sunny and cold in the morning, with the track warming up by the afternoon session despite a light cloud cover. For the morning test, the session began with ten minutes of Safety Car procedural training, before the cars got to work in earnest at 9:10 AM JST.
The programmes for most teams shifted towards race simulations over one-lap runs, and early in the morning session it was the Nissan GT-Rs, which struggled for most of Saturday for outright pace, which climbed to the top. The #12 Calsonic Impul GT-R of Daiki Sasaki & Jann Mardenborough led the way, with Sasaki posting a 1:18.800, good enough for 4th once the session ended.
35 minutes into the session, Kogure put the Keihin NSX at the top of the leaderboards with a 1:18.223, followed by the #100 Raybrig NSX-GT of Naoki Yamamoto, taking over on Sunday from Jenson Button, with a 1:18.773.
Kogure and Yamamoto found even more pace in a matter of minutes. By the end of the first hour, Yamamoto had improved to a 1:18.256 to finish in 2nd, and Kogure ended the morning test with a 1:18.177, good enough to put the two Bridgestone-clad Hondas 1st and 2nd on the leaderboards. Defending GT500 champion Ryo Hirakawa placed third in the #1 KeePer TOM’s Lexus LC500, with a 1:18.770.
On the GT300 side of things, sophomore driver Sho Tsuboi set the early benchmark in the #25 Hoppy Toyota 86 MC, a 1:25.592, in the first hour of the session. It looked as if that time would stand at the top when the chequered flag fell.
However, on his final flying lap, Hiroki Katoh in the #2 Syntium Apple Lotus Evora MC supplanted his fellow Mother Chassis runner at the top, with a 1:25.584, edging out the Hoppy 86 by just 0.008 seconds, and continuing Cars Tokai Dream28’s encouraging form from Saturday.
The #21 Hitotsuyama Audi R8 LMS of Richard Lyons, and the #26 Taisan SARD R8 of Shintaro Kawabata, were right behind them in 3rd and 4th, another encouraging result from Audi after their tough 2017 season.
After an intermission, the afternoon session began with a simulated rolling race start. This would be the first time that the GT Association (GTA) stewards would enforce the series’ more stringent enforcement of race start formations.
Once the afternoon session got underway at 13:45 JST, teams began locking in on their long-run programmes.
Daiki Sasaki set a quick lap of 1:18.613 aboard the #12 Calsonic GT-R, which would then be improved to a 1:18.542 within the first half-hour of the test. Because of the shift in priorities, that would go on to stand as the best time in the afternoon session, putting Nissan at the top in Japan just hours after their American-based partners at Extreme Speed Motorsports won the 12 Hours of Sebring.
Second was the #1 KeePer TOM’s LC500, driven by defending champion Nick Cassidy, with a 1:18.837. And just behind Cassidy in third was the #23 Motul Autech NISMO GT-R of Ronnie Quintarelli, with a 1:18.853.
In GT300, the top time was posted by the #61 Subaru BRZ R&D Sport of Hideki Yamauchi, a 1:26.082. Natsu Sakaguchi in the #5 Team Mach Toyota 86 MC was second with a 1:26.242, ahead of reigning champion Nobuteru Taniguchi aboard the #0 Goodsmile Hatsune Miku Mercedes-AMG GT3, with a 1:26.353. From this test session, the Mother Chassis teams appear to have the edge over the field for now.
The first official tests of the refreshed 2018 Nissan GT-R NISMO GT3, and the new Honda NSX GT3, didn’t go entirely to plan. The Gainer-run Nissan GT-Rs could do no better than 16th overall on Saturday, and 18th on Sunday, from the Yokohama-clad #10 Gainer Tanax triple a GT-R (Kazuki Hoshino/Hiroki Yoshida). The #34 Modulo Kenwood NSX GT3 (Ryo Michigami/Hiroki Otsu) was the best of the two Hondas as expected, but they were 17th overall on Saturday, 19th overall on Sunday.
Neither got below the high 1 minute 26 range, but the second round of pre-season testing, at the high-speed Fuji Speedway on March 24-25, could potentially shake things up in the GT300 running order.
15,538 spectators attended the two days of testing at Okayama International Circuit.