- THE LAB
- TRACK RECORD
- WE TAKE A LEXUS LFA FOR A TURN AT SHIBETSU,
- THE VAST PROVING GROUND IN NORTHERN JAPAN,
- WHERE SOME 200 TEST-DRIVERS PUT THE LATEST MODELS
- THROUGH THEIR PACES EVERY DAY
A jet aircraft making an emergency landing on a racetrack surrounded by forest might sound like an action sequence from a James Bond movie, but the Shibetsu Proving Ground, one of Lexus’s test facilities in Japan, is more than equipped for such a stunt. The vast 3.59-square-mile site is outfitted with a staggering 2.4-mile-long straight, more than ample room for a jet, let alone the large quantity of test cars that take to its routes each year.
The Shibetsu Proving Ground — or SPG — opened in 1984 after six years of planning and building. Rumor has it that the scale of the construction was so large, the Soviets mistook it for a fort being created by the Japanese. Hidden behind heavy security and tall metal fences are five circuits, each varying in size and function. The longest of these is 6.2 miles. The tracks are surrounded with tiny villages of buildings and facilities, used to assess and maintain all kinds of vehicles, ranging from production cars to highly confidential prototype models. Shibetsu’s reputation precedes it — simply speaking, it is the best and biggest proving ground in Asia. Perhaps contrarily, Shibetsu itself is an unremarkable little town located near Asahikawa, Hokkaido, with a population of just over 20,000. Despite its small size, it has its own place in the history of the automobile: the very first Lexus model, the LS 400, was developed from a basic idea into a full-fledged luxury sedan at this proving ground during the 1980s.
“We shipped several cars to SPG in 1985 to kick-start the research and development of the LS 400,” recalls Hideki Watanabe, now employed as chief engineer at Lexus. “Back then, the construction of the main circuit wasn’t complete, but the 2.4-mile-long high-speed straight had been built already. So we test-drove prototypes on that straight — day in, day out.”
The ability to try out new Lexus models on high-speed straights like the one at Shibetsu was imperative in helping the nascent brand set its sights on the overseas market in the early days, allowing Lexus engineers to tweak and test their vehicles to meet the demands of foreign customers. “Before SPG, we did much of the high-speed testing overseas and the fine-tuning at home, but this approach wasn’t ideal,” Watanabe recounts. “There were times when our Japan-based engineers struggled to get to grips with feedback from, say, Europe — simply because they were not present at the testing. Then SPG came into the picture, rectifying that situation, so we could all be on the same page, all the time.”
A high-speed circuit on home soil did not take long to bear fruit for Lexus. First, Shibetsu helped reduce costs. It also sped up the research and development process, with the majority of testing now done in-house. When it came to the LS 400, the proving ground’s biggest contribution was helping forge superb aerodynamics and an exceptionally quiet cabin environment. Lexus was aiming to roll out the LS 400 into the premium segment market as a full-size luxury sedan, so finding a synergy between excellent driving performance and interior comfort was a must. Thanks to SPG, the engineers could analyze and perfect the vehicle’s acceleration, movement and noises at speeds as fast as 155 mph, impossible on the shorter domestic courses previously used by Lexus.
Leafing through a thick bundle of aged A4 paper, on which all manner of handwritten LS 400 data is noted in various scrawls (as it was in the days before personal computers), Watanabe recounts: “We made an especially huge effort in streamlining the exterior’s architecture. As part of the process, we put clay on the steel body of a prototype and then sculpted it millimeter by millimeter until we were all happy with the result. We built and tested seven different kinds of exterior.”
The efforts of the development team paid dividends, with the LS 400 production model achieving the drag coefficient of 0.29. “Given that it is still a challenge to break through the wall of Cd 0.25, you can see our LS 400 was exceptionally good aerodynamics-wise, and it was all thanks to Shibetsu,” adds Watanabe with a smile.
The high-speed straight of the main circuit isn’t Shibetsu’s only cutting-edge feature. At the end of the straight track sits the 450R, a 450-meter-radius turn, with a bank angled at 43 degrees. This turn is designed in such a way that the driver can negotiate it without applying brakes at a cruising speed of 125 mph. Then comes the 1000R S-shaped bend, followed by the 250R, another superfast turn.
The four other circuits at Shibetsu also have their own special features — such as tree-lined country roads — to help put vehicles through their paces. To examine the effects of certain road conditions on Lexus vehicles, more than 20 road surfaces unique to different regions and countries around the world, such as the German autobahns, have been duplicated and installed on several sections of the courses at Shibetsu. All in all, SPG brims over with everything the Lexus automobile engineer — or takumi — needs to hone the vehicles.
Shibetsu’s geographical location in the north of Japan, beset by extreme weather conditions throughout the year, also makes it globally unique as a testing ground.
Following the kaleidoscopic rainbow of fall leaves comes the harsh winter, when heavy snow is accompanied by subzero temperatures, sometimes reaching as low as minus 4 degrees Fahrenheit. The town sees about three feet of snow on average per year, and that depth can double in the surrounding mountains. The severity of the winter weather conditions may seem inhospitable to some, but the engineers admit that the bitter cold and heavy snow are actually to their advantage.
“This location was chosen especially for its weather conditions,” says Fumitaka Nakamura, general manager at SPG. “The whole area is covered with snow over a period of four months, starting in November, with the peak snowfall coming between January and February.”
During the winter, the main circuit is closed, but Circuit No. 3 — a midsize course — comes into its own when its snow-covered surface is used for high-speed testing. Facilities to assess brakes, radiators and batteries in freezing environments are taken advantage of.
“It’s harsh on humans, but these tests in extremely cold conditions are essential to ensure the quality and durability of our products,” adds Nakamura.
Given the nature of the work that happens at SPG, thorough safety and security measures are put in place throughout the site. CCTV keeps a watchful eye over all corners of the proving ground at the control center. Should an accident occur, everyone on the ground carries a walkie-talkie so that help can be summoned in no time at all. Even the plain-looking guardrails have received special treatment to help reduce the severity of injury in case a car crashes.
TEXT BY SHOGO HAGIWARA AND
PHOTOGRAPHY BY KOHEI TAKE