Who Remembers The JUN Akira Supra?

We’ve all got ‘em – videos that sparked our love for cars or channelled our interests in a particular direction.

I could name a few, but one that stands out is a 21-second clip of a bright yellow MkIV Toyota Supra built by JUN, power-sliding at Tsukuba Circuit. I’m not sure where I first saw it online, but in 2001 – four years before YouTube was a thing – you can bet I risked the prospect of 25 to life by downloading the bootlegged clip.

Thankfully, you don’t have to.

So imagine my joy, when a few years later, I caught a glimpse of what appeared to be that very same car parked in a gravel lot across the road from JUN’s Iruma shop.

What I didn’t know at the time was that this was the same Supra that had graced the covers of Max Power and Super Street magazines in late 2001, with a somewhat different outward appearance. A Supra that had reached the mind-numbing top speed of 401.20km/h (249.292mph) on the Bonneville Salt Flats in Utah, USA.

How did I end up here? Back in 1999, I met JUN Auto Mechanic head Susumu ‘God Hand’ Koyama in New Zealand when he travelled here to compete in the Option Speed Trial with the JUN Super Impreza GC8 – a 580ps (572hp) beast that hit 309.1 km/h on a long and straight but bumpy and wet backroad. I knew I had to visit JUN, and in 2004, I came to Japan and was able to make it happen.

More than 20 years later, I’m still humbled to have received personal tours of JUN’s Nerima shop in Tokyo and JUN Auto Works/Auto Mechanic in Saitama from the company’s founder, Junichi Tanaka.

I didn’t get to spend much time with the Supra – it was the end of the day, and I had a train to catch back to Tokyo. But I was lucky enough to get the car moved into a little open space in the parking lot for a few photos.

JUN was founded in 1980, but its parent company’s history dates back to 1946. After World War II, Tanaka-san’s father founded Tanaka Industrial Co., repurposing machinery used for Japanese warplanes for automotive applications. For his entry into Japan’s performance car tuning industry, Tanaka-san hired Koyama-san, a talented young mechanic, to head up operations, and JUN as we know it was born.

The latest turbocharger technology was the heart of JUN’s operations, and the company quickly built a name for itself by building some of Japan’s fastest and most powerful cars. Tuning car top-speed trials held at the now defunct Yatabe Test Track by Option magazine in the ’80s became an early focus for Koyama-san. Then, in 1990, he took JUN to the global stage with multiple appearances at Bonneville in different cars. In 2001, JUN returned to the salt flats with its ‘Akira Supra’ – a demo car build started three years earlier from a stock 1993 Toyota Supra RZ.

Unlike most cars in Bonneville’s 200mph Club, JUN’s Supra wasn’t a purpose-built, tube-framed race car. It was a modified street car with some extra go-fast bits added (and removed) to allow it to reach 400km/h – a number Koyama-san had seen on the salt with previous builds.

Around the same time JUN was in the USA with the Akira Supra, the bootlegged clip of the car power-sliding at Tsukuba made its way online, now known to have been ripped from Video Option Vol. 76, which came out in 2000. Thinking back, this might have been the very first ‘viral’ video to emerge from Japan’s tuning scene, which was still largely a mystery at the time.

Thankfully, Option officially uploaded the full three-minute segment to YouTube a few years ago, so you can watch that by pressing the play button above. As it turns out, the Akira Supra had been brought to Tsukuba to see how fast it could lap the circuit, and on a warm-down lap, Option test driver Eiji ‘Tarzan’ Yamada decided to have some fun…

Not long after I first saw the power-slide clip, a friend loaned me a Video Option VHS tape from, I’m guessing, around 2000 too. In the grainy footage, the Akira Supra was filmed ripping through the gears along the Tokyo Aqualine at over 300km/h – the Wangan benchmark of the golden era. It just got better.

Even before I knew of its Bonneville exploits, the Akira Supra embodied everything amazing about the Japanese tuning scene at the time. It was a street car that could hit 300 km/h with ease and drift. It had a 2JZ-GTE engine built up to 3.2L with JUN prototype parts – forged crankshaft, forged rods and pistons, performance cams – and a T88 turbo. Gear shifts were made through a sequential gearbox, practically unheard of in street cars, and it was unmistakably a JUN creation with functional exterior mods and that signature yellow paint.

For the Bonneville attempt, the 2JZ engine was completely overhauled. In addition to strengthening and modifying the engine base for more power, Koyama-san added twin Trust/GReddy SPL T78-29D-14cm turbos, a prototype JUN intake manifold, and a fuel system up to the task. That system included a 120L tank, five Bosch Motorsport fuel pumps, and a dozen JUN 890cc injectors. Tuned through an HKS F-CON V Pro engine management system, the setup made nearly 1,400ps (1,380hp).

The driveline retained the same 6-speed Holinger sequential gearbox it had previously been fitted with, but a 2.238:1 final drive ratio was used in the rear end to ensure the Supra could mechanically hit 400 km/h. Combined with its aerodynamic modifications and a full flat steel underbody tray, the Supra averaged 240.192mph (386.55 km/h) over two runs in the E/BGCC class. Hitting 401.20km/h on one of the runs is what it’s remembered for though.

When it returned from Bonneville, the Akira Supra was converted back to its street car setup, with a single Trust/GReddy T88-34D-22cm turbo, a milder cylinder head specification, a pared-back fuel system, and a more road-friendly diff ratio. In this form, the power output was up to 950ps (937hp), running around 1.7bar (25psi) of boost. That’s the spec you see here.

The street version of the Akira Supra – JUN’s original look for the car – perfectly reflected the late-’90s/early-’00s Japanese tuner style. The front bumper, vented and bulged hood, aero mirrors, and GT wing were all JUN parts, while the rear diffuser was a RE Amemiya piece. Completing the vision were gold 18-inch Advan Model 6 wheels – the same ones used at Bonneville – wrapped in Yokohama Advan semi-slicks.

Since the Supra hadn’t been cut up in its transition from road car to salt flats racer, it was easy for JUN to return it to street-spec. Despite its race upgrades, like a welded Cusco 10-point roll cage and a Recaro SPG seat, it benefited from some comforts, such as a full dash, front carpet, and door cards. Also kept in place was the originally-fitted suite of GReddy gauges, plus its then-state-of-the-art Stack 8100 digital dash display.

In the years following my 2004 encounter with the Akira Supra, nothing much was heard about the car, so I assume it spent more time parked up in the lot. Then, in 2011, JUN gave the Supra a full overhaul – repainting it silver with new yellow and orange graphics and refreshing the powertrain for circuit use.

Two years later, in early 2013, JUN put the car for sale, but it took until late 2014 for a purchase to be made. That seems like a long time given the asking price, which you might want to sit down for: ¥6,000,000 before tax – that’s just US$40,000 in today’s money.

I’d love to know where the Supra ended up. There’s online chatter that mentions Australia, but I can’t confirm it. Hopefully someone out there can shed some light on its location and current form.

One thing’s for sure: of all the tuner cars built in Japan over the years, JUN’s Supra might just be the greatest. It was an all-rounder like no other.

Unfortunately, Tanaka-san passed away in 2019, aged 76, after an illness, and Koyama-san, who had battled illness for years, passed away in 2022, having gone on to found Koyama Racing Labo in 2009/2010. While these icons of Japanese performance tuning are sadly gone, JUN’s legacy will live on forever through cars like the legendary Akira Supra.

Brad Lord
Instagram: speedhunters_brad