What you can customize on a GR86
The Toyota GR86 is built to be modified. Unlike some sports cars that come locked down, Toyota designed this car expecting owners to change wheels, suspension, exhaust, and interior trim. You can customize almost anything: the exterior appearance through body kits and paint, the interior through seat covers and steering wheels, the engine through tuning and intake upgrades, and the suspension through coilovers and sway bars. The question is not whether you can modify it, but which modifications make sense for how you actually drive.
Most GR86 owners start with bolt-on parts — things you can install without welding or permanent changes. These include wheels, tires, exhaust systems, air filters, and suspension components. From there, some owners move into more involved work like engine tuning, turbocharging, or body panel replacement. The car's aftermarket support is strong because it shares a platform with the Subaru BRZ, so parts designed for one often fit the other.
Key Takeaways
- Bolt-on modifications like wheels, exhaust, and suspension parts require no permanent changes and can be reversed if you change your mind.
- Engine tuning through an ECU tune can add horsepower but may void your warranty, so check your dealer's policy first.
- Suspension upgrades like coilovers and sway bars change how the car handles and should be matched to your driving style and road conditions.
- Interior customization through seat covers, steering wheels, and shift knobs is purely aesthetic and does not affect performance or warranty coverage.
- Turbocharging and engine rebuilds are permanent modifications that require professional installation and significantly increase cost.
Exterior modifications: wheels, body kits, and paint
Wheels are the most visible and most common first modification. The stock GR86 comes on 18-inch wheels, and most owners either stay with 18s or drop to 17s for better ride quality and cheaper tire replacement. Brands like Enkei, Rays, and Rotiform make wheels specifically for the GR86 platform. When you choose new wheels, you also need new tires — the stock size is 215/40R18, but different wheel sizes require different tire sizes. A tire shop can tell you what sizes work with your chosen wheel diameter.
Body kits change the car's visual profile by adding or replacing front splitters, side skirts, and rear diffusers. These are usually fiberglass or plastic and bolt on over the stock panels. Some owners also add a front lip spoiler or a ducktail rear wing. These modifications are purely visual unless they are designed to improve aerodynamics at high speed — most bolt-on kits do not. Paint customization ranges from a full respray in a new color to vinyl wraps that cover the entire car or just sections like the roof or hood. Vinyl wraps are reversible; repainting is not.
Suspension and handling upgrades
The GR86's suspension is tuned for comfort and everyday driving, not track performance. If you want a stiffer, more responsive feel, coilovers are the standard upgrade. Coilovers replace the stock springs and shocks with a single unit that lets you adjust ride height and stiffness independently. Brands like Tein, Stance, and Ohlins make coilovers for the GR86. Installation takes a few hours at a shop, and costs range widely depending on the brand and whether you want adjustable damping.
Sway bars (also called anti-roll bars) reduce body roll in corners by connecting the left and right sides of the suspension. Upgrading to a thicker sway bar makes the car feel more planted but also slightly harsher on rough roads. Most owners pair sway bar upgrades with coilovers or lowering springs. Strut braces, which connect the shock towers across the engine bay, add stiffness to the chassis. These are bolt-on and relatively inexpensive, though the performance gain is small compared to suspension work.
Engine tuning and power modifications
The stock GR86 makes 228 horsepower. An ECU tune — a reprogramming of the engine computer — can add 15 to 25 horsepower by adjusting fuel timing and boost pressure. Tuning companies like Ecutek and OpenFlash offer GR86-specific tunes. A tune is reversible: if you sell the car or want to return to stock, the original software can be restored. However, some dealers will not service a tuned car under warranty, so check your dealer's policy before you tune.
Intake and exhaust upgrades improve airflow but add less power than a tune. A cold air intake pulls cooler air into the engine, and an aftermarket exhaust system reduces backpressure. Together they might add 5 to 10 horsepower and improve throttle response. These are bolt-on modifications that do not void warranty at most dealers. Turbocharging is a permanent, expensive modification that requires professional installation and adds significant complexity. A turbo kit can double the car's power output but costs $4,000 to $8,000 in parts plus installation labor.
Interior customization and comfort upgrades
The interior is where you spend every drive, so many owners personalize it first. Seat covers protect the stock seats and change the look. Aftermarket steering wheels from brands like Momo and OMP offer better grip and a smaller diameter than the stock wheel. A short-throw shifter reduces the distance your hand travels between gears and makes shifts feel quicker. These are all bolt-on, reversible changes that do not affect warranty.
Pedal covers, floor mats, and shift knobs are purely cosmetic. Some owners add a roll cage or racing harnesses if they plan to track the car, though these are permanent modifications that require welding and professional installation. Dashboard trim pieces can be wrapped in carbon fiber vinyl or replaced with aftermarket versions. Lighting upgrades like LED interior bulbs and underglow are popular but check your local laws — some states restrict underglow colors or brightness.
Maintenance and reliability after modifications
Modifications do not automatically break a car, but they do change how the car ages. A tuned engine works harder and may need more frequent oil changes. Lowered suspension on rough roads can wear out shocks faster. Wider, lower-profile tires are more prone to punctures. Track use — even occasional — wears brakes, tires, and suspension much faster than street driving. If you modify your GR86, budget for more frequent maintenance and be honest with yourself about how hard you drive it.
Keep records of all work done. If you ever need warranty service, the dealer will want to know what has been changed. Some modifications are dealer-friendly; others are not. Bolt-on parts like wheels and exhaust rarely cause warranty issues. Engine tuning and turbocharging are red flags to dealers because they increase engine stress. If you plan to modify heavily, consider whether you want to keep the car long-term or sell it in a few years — heavily modified cars are harder to sell because buyers have different taste in modifications than you do.
Budget and prioritization: where to start
A full GR86 build can cost $10,000 to $30,000 or more, depending on how far you go. Most owners start small: new wheels and tires ($1,500 to $2,500), then an exhaust system ($500 to $1,200), then suspension work ($1,500 to $3,000). This progression lets you feel each change and decide what matters to you before spending on more expensive work.
Think about your actual use. If you drive on rough city streets, lowering the car and stiffening the suspension will make it uncomfortable. If you track the car, suspension and brakes matter more than paint and wheels. If you just want it to look different, exterior and interior changes give you the most visual impact for the money. The best modification is the one that matches how you actually use the car, not the one that looks best in photos.
Frequently Asked Questions
Will modifying my GR86 void the warranty?
It depends on the modification and your dealer. Bolt-on parts like wheels, exhaust, and air filters rarely cause warranty issues. Engine tuning and turbocharging are more likely to be flagged. Check with your dealer before you modify — some are more modification-friendly than others, and policies vary by region.
Can I install modifications myself, or do I need a shop?
Wheels, tires, and some interior parts you can do yourself if you have basic tools and mechanical confidence. Suspension work, exhaust installation, and engine tuning should go to a professional shop. Mistakes in suspension or engine work can be expensive to fix and unsafe to drive.
What is the most popular first modification for a GR86?
New wheels are the most common first change because they are visible, reversible, and do not require mechanical work. An exhaust system is a close second because it improves sound and adds a small power bump. Both are relatively affordable entry points into modifying the car.
Does lowering a GR86 hurt the ride quality?
Lowering springs reduce ride height but keep the stock dampers, which can feel harsh on bumpy roads. Coilovers let you adjust stiffness, so you can lower the car and still have a comfortable ride if you tune the damping correctly. The trade-off is cost — coilovers are more expensive than springs alone.
How much horsepower can I realistically add without major engine work?
An ECU tune adds 15 to 25 horsepower. Intake and exhaust together add another 5 to 10. So realistically, 20 to 35 horsepower with bolt-on parts and tuning. Turbocharging or engine rebuilding can double the power, but those are major, expensive modifications that require professional installation.