Introduction

The A90 Supra has quickly earned its place as a modern icon among driving enthusiasts. Its combination of a BMW-sourced B58 turbocharged inline-six, ZF eight-speed automatic, and a Toyota-tuned chassis offers a superb foundation for track work. But turning a capable street car into a reliable, fast, and safe track tool requires more than just bolting on parts. You need a systematic approach that prioritizes safety, then refines handling, and finally unlocks the engine’s potential. This guide walks through the essential modifications and upgrades to build a genuine track-ready A90 Supra that you can trust session after session.

Safety First: Preparing the Cockpit and Chassis

Before chasing lap times, you must ensure that both you and the car can withstand the rigors of high-speed driving. Safety modifications protect you in a crash and also stiffen the chassis for better feedback and consistency.

Roll Cages and Chassis Stiffening

A full roll cage significantly increases structural rigidity, improving suspension response and occupant protection. For A90 Supras, a custom or bolt-in cage tied to the chassis at multiple points is ideal. Make sure any cage complies with your local track or sanctioning body rules (for example, SCCA or NASA). If you plan to keep the car street-legal, consider a half cage with a removable crossbar. Pair this with a strut tower brace—even a simple aluminum bar across the front towers helps reduce flex during cornering.

Seats, Harnesses, and Brackets

The stock seats offer decent comfort but lack the lateral support needed for sustained cornering. Replace them with a fixed-back racing seat from brands like Recaro, Sparco, or Bride. Pair the seat with a sidemount bracket that positions the seat as low and central as possible. For harnesses, use a 6-point camlock harness (e.g., Schroth or Willans) to keep you secure. Never use a harness without a proper harness bar or cage mounting points, and always install a Hans-type device compatible with your harness setup.

Fire Suppression and Safety Equipment

A hand-held fire extinguisher mounted within easy reach of the driver is a minimum requirement. For serious tracking, a plumbed-in fire suppression system (e.g., Lifeline or AFFF) adds a layer of security. Also equip yourself with a fire-resistant driving suit, gloves, and shoes. A properly installed kill switch (battery cut-off) inside the cockpit allows marshals to shut down the car quickly in an emergency.

Stopping Power: Brake System Upgrades

Stock brakes may fade after a few hot laps. Upgrading them is one of the most impactful safety and performance modifications you can make.

Brake Pads and Rotors

Swap the stock pads for a dedicated track pad compound. Brands like Ferodo DS2500 or Pagid RS14 offer high initial bite and resist fade. Combine them with two-piece floating rotors (e.g., Girodisc or StopTech) that dissipate heat more effectively than one-piece stock rotors. If you repeatedly overheat the brakes, consider a big brake kit (BBK) from Brembo, AP Racing, or Essex Parts that uses larger rotors and multi-piston calipers.

Brake Fluid and Cooling

Standard street brake fluid boils quickly under track abuse. Replace it with a high-temp fluid like Motul RBF 660 or Castrol SRF. Then, improve brake cooling by installing ducting that routes air from the front bumper to the brake rotors. Some A90 owners use aftermarket brake backing plates or cut factory dust shields to allow more airflow.

Handling and Suspension

A Supra that corners flat and communicates clearly inspires confidence. Every suspension component influences the car’s balance.

Coilovers vs. Adjustable Shocks

Coilovers (example: KW Variant 3, Ohlins R&T) let you adjust ride height, damping, and often camber. They are the most direct way to lower the center of gravity and dial in handling. If you want to retain the factory electronic damping control, look into plug-and-play adaptive suspension kits like the Bilstein B6 Damptronics. For pure track use, a set of race-oriented coilovers with remote reservoirs and multiple adjustment ranges is best.

Anti-Roll Bars and Bushings

Upgrading the front and rear anti-roll bars to stiffer units (e.g., Swift, Whiteline) reduces body roll and improves transient response. Adjustable bars let you fine-tune understeer/oversteer balance. Replace rubber suspension bushings with polyurethane or spherical bearings for sharper steering feedback. The rear subframe bushings in the A90 are known to flex; aftermarket solid or semi-solid bushes tighten up the rear end under power.

Alignment Geometry for Track

Proper alignment is critical. A typical track alignment for the A90 Supra includes: -2.5 to -3.0 degrees of front camber, -1.5 to -2.0 rear camber, 0 to 0.15 degrees total toe-in front, and 0.1 to 0.2 degrees total toe-in rear. These settings maximize tire contact patch and stability under braking. Speed Academy has a detailed guide on aligning the A90 Supra for track use.

Tire Selection: The Ultimate Grip

Tires are the single most effective performance upgrade. For dry track days, choose extreme performance summer tires like the Michelin Pilot Sport Cup 2 R, Yokohama A052, or Continental ExtremeContact Force. For beginners, a 200-treadwear tire such as the Hankook RS4 or Falken RT660 offers good lifespan and predictable grip. Always monitor tire temperature and pressure with a pyrometer and adjust for ideal contact patch.

Weight Reduction Strategies

Every pound removed improves acceleration, braking, and cornering. Start with the easiest: remove the spare tire, jack, trunk liner, and rear seat (if equipped). Replace the stock battery with a lightweight lithium-ion unit. Swap the heavy factory exhaust for a titanium system, and consider carbon fiber body panels (hood, trunk) to shed more weight. Keep safety in mind—never remove critical structural elements.

Power Modifications

The B58 engine responds well to tuning, but reliability requires supporting mods.

ECU Tuning: Unlocking Potential

A flash tune via platforms like MHD (on bench) or ECUtek (via OBD or bench) can add 60–100 wheel horsepower on pump gas with no other changes. For the A90, choose a reputable tuner who understands the limits of the stock fuel system. A stage 1 tune (93 octane) with a cold air intake and cat-back exhaust yields a solid gain. For more power, move to stage 2 or 3 with upgraded downpipe, intercooler, and fueling.

Intake and Exhaust Upgrades

A high-flow cold air intake (e.g., Eventuri, MST) reduces restriction and adds induction sound. Pair it with a catless or high-flow catted downpipe to free up exhaust flow. A full cat-back exhaust (Injen, AWE, Milltek) further reduces back pressure and drops weight. On many B58s, the stock turbo backpressure can be improved with a better mid-pipe and muffler delete.

Intercooler and Cooling Systems

Heat soak kills performance. Upgrade the stock intercooler to a larger bar-and-plate unit (e.g., Wagner Tuning, CSF) to lower intake air temperatures. Also consider an upgraded radiator (e.g., CSF or Mishimoto) and an oil cooler (if your car does not have the factory ZF oil cooler). The A90’s water-to-air intercooler system can be improved with a larger heat exchanger and electric water pump to maintain flow during hot lapping.

Turbocharger Upgrades

For serious power (500+ whp), a hybrid or larger turbocharger is necessary. The B58’s twin-scroll turbo can be upgraded to a Garrett G30-770 or Pure Turbo Stage 2. This requires upgraded fuel injectors, low- and high-pressure fuel pumps, and a custom tune. It’s a major investment but transforms the car’s top-end power. Pure Turbos offers specific upgrades for the A90 Supra.

Supporting Mods: Drivetrain and Fluids

A track car must endure high loads. Upgrade the transmission cooler (for the ZF8) to prevent overheating. Swap to high-temp transmission fluid (e.g., Red Line D6 ATF). For rear differential, consider a limited-slip differential upgrade (OS Giken, Quaife) if your car does not have the optional factory LSD. Use high-quality synthetic engine oil with a higher viscosity (0W-40 or 5W-50) for track use, and change it frequently.

Conclusion

Building a track-ready A90 Supra is a rewarding process that transforms a great sports car into a purpose-built machine. Start with safety: cage, seats, harnesses, and fire suppression. Then upgrade brakes and suspension to handle higher speeds and forces. Finally, add power modifications with a tune and supporting cooling improvements. Always consult professionals for installation and tuning, and check Toyota’s official site for any technical service bulletins relevant to your model year. With the right combination of parts, your Supra will deliver consistent, thrilling lap after lap.