Australia would probably be the last place you’d expect to stumble across a Super GT race car, but thanks to some persistent negotiations, Toyota Australia was able to bring over a piece of automotive history: TRD’s infamous GT500 Supra.
When I caught wind of it being in the country, the first thing I thought was that it was probably a rolling shell; a ‘dummy’ replica with no running gear used for promotional exercises. I was wrong though, and credit to Toyota Australia for managing to wrestle the Chassis 534N #26 from the grasps of its protective Japanese engineers.
Although this Supra is now retired, TRD still closely guard its engineering secrets and were reluctant to let it out of their sights. It was in Australia for just a couple months before it had to go back to Japan, with the only alteration being the removal of its ECU (so that no one abroad could fire it up).
This particular Supra contested two championships and also served as the primary R&D vehicle for TRD’s prototype GT500 components. Heavy stone chips and battle scars litter the front bar. A source within Toyota Australia informed me that they considered repainting the vehicle so it would be more presentable when it toured our Auto Salon events, but I’m glad they left it as is.
With its carbon hood removed you can see that this Supra isn’t powered by a conventional inline-six 2JZ. This particular Supra is fitted with a four-cylinder 3S-GTE (towards the end of the Supra’s tenure in Super GT the V8 3UZ-FE was preferred).
Super GT is heavily regulated to ensure parity, and the Supra is fitted with a 43mm intake restrictor to cap its power output. Fabricated wheels tubs allow the chassis to be dropped as low to the ground as possible, while the compact 3S-GTE gave TRD’s engineers the freedom to move the engine rearwards. In comparison to the wheel arches you can also see how low the 3S is mounted, with the bulk of the engine’s weight below the wheel centerline.
Shovelling cool air to the intercooler and radiator is only half the job; drawing the ‘spent’ air out of the engine bay is equally vital. A dry carbon partition is fitted behind the front bar to create individual streams for each core, with deeply-sunk louvers in the hood then expelling the air out and over the vehicle.
Meticulously put together by Toyota Technocraft, each 3S engine is given its own identification number (as you can see this one is #107). In the event of a mechanical failure, this allows TRD to trace which batch the offending component came from.
The 19×13-inch magnesium RAYS Wheels are dwarfed by the monstrous AP Racing brakes. Due to the enormous temperatures generated by the brakes, regulations allow for the calipers to be cooled via a recirculating-fluid system.
The wafer-thin rear hatch is fabricated from carbon honeycomb and Lexan, and can be easily carried with one hand. The hatch has cut-outs for the rear wing, which is bolted directly to the chassis. The chromoly roll-cage links all four corners, passing through the firewall that separates the boot from the cabin. The firewall is a mandatory fitment as the fuel cell resides in the rear-section.
The floor between the chassis rails has been cut away to make room for the cantilever suspension and its aluminum cradle. The shock absorbers are custom units from Ohlins, with the remote reservoirs positioned towards the center of the car to improve weight balance. To ensure that nothing has been overlooked, all of the bolts are marked with a pink dot once they’ve been torqued correctly.
The two female plugs are for refuelling: the rig connects just below the rear wing, with one hose pumping fuel and the other providing ventilation.
In spite of how large this Supra is, the cabin is extremely tight and claustrophobic. You sit incredibly low with minimal side vision. The steering wheel nestles close to your chest and the massive banner on the windscreen makes it seem like you’re peering out of a letterbox slot.
The driver is able to adjust the brake-bias to suit a specific section of the track or to compensate for tire wear or diminishing fuel loads. The knob is located within easy reach and is brightly coloured for maximum visibility. As driver changes are part of Super GT racing, the steering wheel flips up on a hinge to make getting in and out somewhat easier.
In the footwell is the Supra’s raised pedal box and aluminum heel shelf, with all contact surfaces covered in skateboard grip tape to prevent any slipping. In-cabin temperatures are a real issue for the driver, particularly in the endurance rounds. Flameproof ducting is routed beneath the dash to provide some respite, while the transmission tunnel has been covered in insulation.
GT500 cars generate the majority of their downforce through ground-effects. TRD’s Supra features a flat floor and low skirting so that air is propelled cleanly towards the rear diffuser. Like almost every other part on this Supra, the diffuser is made from dry carbon.
While it was a privilege to have full access to shoot this legend, moving it around the studio was an absolute nightmare. Go-jacks couldn’t be used as the Supra is simply too low, so it had to be done the hard way. And with 13-inch wide slicks and a turning circle akin to that of a stretch limo, getting the Supra into position for each shot required a 25-point turn!
Words by Charles Kha
Photos by Mark Pakula