Toyota GR Yaris Performance Tuning Kits

Toyota GR Yaris Performance Tuning Kits – cooling, airflow and drivability upgrades for the GR Yaris platform

The Toyota GR Yaris Performance Tuning Kits range targets the practical limits seen on hard-driven GR Yaris cars across Gen 1 (2020–2024) and Gen 2 (2024+): rising IAT on repeated pulls, pre-turbo restrictions, elevated oil temperatures under load, plus driver-feel and exhaust character tuning.

You’ll find both hardware and software, so it helps to build a balanced package: intercooler + turbo inlet + airbox/inlet feed for consistent cold-air supply, then oil cooling and a diverter/dump valve solution for dependable boost behaviour.

Technical Basics

The FMINT25 intercooler is a stock-location upgrade described with a race-spec tube-and-fin core and high-flow cast end tanks. The listing references gains of 10 bhp and 10 lb/ft, temperature drops up to 20°C, plus a volumetric increase of 100%+ and frontal area increase of 40%+.

For the pre-turbo tract, the FMTIA8-STOCK kit (with optional TTE500) is described as a complete inlet package: CNC 6082 adaptor, two 5-ply silicone hoses and a mandrel-bent alloy hard pipe. It states an increase from 48→63 mm at the turbo entry and mentions average dyno gains of 4–5 bhp (up to 10 lbft), with “no EML” highlighted.

On the airbox side, FMINDK43 replaces the upper airbox while retaining the OEM lower section, using carbon fibre and a pleated performance filter. The description notes an 80→89 mm diameter change (around 20% volumetric increase) and cites peak improvements of 13 bhp and 8 Nm on a stock ECU, with careful MAF sensitivity testing.

The Toyota Yaris GR Inlet Duct is a carbon inlet feed designed to improve the cold-air path to the stock airbox, developed using 3D scans and CAD. The listing describes prepreg 2x2 twill carbon formed in an autoclave with a UV-resistant gloss finish, aiming to reduce temperature fluctuation during track or rally-style driving.

For boost control, the FMDV34A dump valve is described for the electronically controlled bypass valve setup (OE 7.04654.08). It’s offered as atmospheric or factory-style recirculating, using a piston-based billet construction to avoid diaphragm failures while retaining OEM ECU control.

Oil temperature management is handled by the FMOC12 oil cooler kit, described as fitting both LHD and RHD vehicles and keeping the factory oil-to-water cooler in place. It includes AN-8 braided lines and a thermostat in the sandwich plate set to open at 85°C; the listing states an approximate total oil capacity of 4.75 L when fitted.

Exhaust-wise, FMSSXTY130MP is listed as a 76 mm non-resonated OPF-back system with 3” (76 mm) pipework and an estimated fitting time of 1.00–1.50 hours. Always check road legality and noise requirements locally before choosing an exhaust configuration.

For an OEM+ finishing touch, FMCAP8-ALL-ALL is a billet 6061 oil cap described as replacing the OE plastic cap used on Toyota 1.6 GR engines. It’s a two-piece design with separate colour/finish choices for the body and insert.

Driver feel can be sharpened with the FMSS5 short shifter, described as delivering a crisper, shorter and more precise shift for GR Yaris and GR Corolla. This won’t add power, but it can improve control during fast-road and track use.

Software is covered by FMREMAP-YARISGR, described as Stage 1 and Stage 2 ECU calibration. The listing references increases from Toyota’s claimed 257 bhp / 360 Nm to 310 bhp+ and 405 Nm (Stage 1) and 320 bhp+ and 420 Nm (Stage 2), treated as target figures that depend on setup and conditions.

Selection Criteria

For consistent performance in warm conditions, start with cooling: FMINT25 plus FMOC12 is a practical foundation to stabilise both charge-air temperature and oil temperature under repeated load.

If your priority is airflow and response, add the FMTIA8 turbo inlet and select the correct adaptor (Stock or TTE500) for your hardware. To improve cold-air feed and airbox flow direction, FMINDK43 and the carbon Inlet Duct are designed to work with the OEM airbox architecture.

For valves, choose by behaviour and sound: FMDV34A supports atmospheric or recirculating operation and is positioned as a reliability-oriented piston solution. Before any remap, fix leaks and ensure the intake/boost path is sealed, as small leaks often reduce real-world gains.

For exhaust, the 76 mm OPF-back system changes character and flow, but legality and noise compliance vary by region. If daily usability matters, consider resonance, inspection requirements and documentation before ordering.

Installation & Maintenance

After an intercooler install, do a leak and clamp check, then re-check after a heat cycle. The FMINT25 listing notes that Gen 2 cars with the water spray option may require an additional bracket, so confirm your equipment level before fitting.

With FMTIA8, sealing on the pre-turbo side is critical for stable metering and response. Even though the hoses are described as suitable around oil mist and O.A.T. coolant environments, correct routing and clamp torque are still the difference between a clean install and boost/driveability issues.

For the FMOC12 oil cooler, verify oil level, leaks and line security after the first heat cycle. Thermostatic operation helps the system work in the intended temperature window, but only if the installation is airtight and properly secured.

FAQ

Do these parts fit GR Yaris Gen 1 and Gen 2?

Several headline items (such as FMINT25, FMTIA8 and FMINDK43) are listed for both Gen 1 and Gen 2. Some equipment differences (like water spray) can introduce extra bracket requirements. Always confirm the product-page fitment notes before checkout.

What does the FMTIA8 turbo inlet change, and how do I pick the adaptor?

FMTIA8 is described as removing restrictions and increasing the turbo-entry size from 48→63 mm. The key decision is the adaptor option (Stock or TTE500), which must match your hardware. If you’re unsure what’s installed, verify first rather than guessing.

Should I run an atmospheric or recirculating dump valve for road use?

The FMDV34A listing describes both options: atmospheric for audible discharge sound and recirculating for a quieter OEM-style feel. For daily use, recirculation is often the safest baseline, while atmospheric is mainly a character choice. In both cases, sealing and correct control strategy matter most.

When is an oil cooler worth it on a GR Yaris?

If you do frequent track sessions, mountain driving or hot-climate hard use, oil temperatures can rise quickly, especially on tuned cars. The FMOC12 kit is described with AN-8 lines and an 85°C thermostat to manage oil temperature more consistently. After installation, always check oil level and inspect for leaks.

Is a 76 mm OPF-back exhaust road legal?

FMSSXTY130MP is listed as a 76 mm non-resonated OPF-back system, meaning it affects the section after the OPF. Road legality and noise limits vary by country and inspection rules, so confirm local requirements and the exact product specification. If in doubt, prioritise documented, vehicle-specific compliant options.

Filter by your goal (cooling, inlet/airbox, valve, exhaust, remap), confirm part numbers and fitment, then order the GR Yaris configuration that matches your build.