Forge Motorsport intercooler for Toyota Corolla GR

• Up to 10 bhp and 10 lb-ft of torque gains
• Temperature reduction of up to 20 °C
• Reduced turbo lag and quicker engine response
• Greater surface area for more efficient heat dissipation
• Race-spec tube-and-fin intercooler core
• Cast high-flow end tanks for optimal airflow and more efficient cooling
• Power and torque gains proven on a dynamometer
• Smoother power curve
• Over 100% greater internal volume
• Over 40% greater frontal area
• Required mounting hardware and fitting instructions included

Forge Motorsport FMINT34 is a high-performance intercooler for the Toyota Corolla GR and a direct replacement for the original part with part number JD127000-1451. The aim during development was to make the best possible use of the space in the original intercooler location and reduce intake air temperature without negatively affecting boost pressure or engine and transmission cooling.

The shape was developed using a combination of scanning, traditional measurements and computational fluid dynamics (CFD) simulations. The end tanks were initially produced using 3D printing and then cast from aluminium using the sand-casting process. Several types of core with different densities and internal and external fin designs were tested during development.

Spacers for mounting to the original bumper bracket are included for installation on the Corolla GR platform. This means installation requires no cutting of the vehicle and is fully reversible. The spacers are made from 6082 aerospace-grade aluminium and protected with an anodised finish. The inlet and outlet ports have also been enlarged, so the kit includes the required boost hoses for optimal airflow on the GR’s three-cylinder engine.

The intercooler uses a tube-and-fin core with an internal divider on the inlet, hot side of the end tank. This ensures more even use of the core’s entire internal volume. Bar-and-plate and various tube-and-fin designs with different fin pitches and heights were also compared during development, including versions with 22 and 17 fins per inch.

Dynamometer testing

Testing was carried out in the United Kingdom on a Toyota Yaris GR using a Maha dynamometer operated by Litchfield. The test vehicle had a complete exhaust system from the turbocharger onwards and a DT UK tuning box. At an ambient temperature of around 19.5 °C, the original intercooler achieved 301.3 BHP and 286.4 lb-ft of torque. After the third run, the intake air temperature quickly increased to almost 58 °C, while power dropped to 295 bhp and torque to 278 ft/lb.

The first test intercooler with a bar-and-plate core was tested at a dyno cell temperature of 22.1 °C. On the third run, it achieved 304.4 BHP and 295.5 lb-ft of torque, while intake air temperature fell to 44 °C.

The second test used a tube-and-fin core with a very dense external fin arrangement. At a higher dyno cell temperature, it achieved 304.1 BHP and 297.6 lb-ft of torque, while intake air temperature did not exceed 46 °C on the third run.

The final version has a slightly smaller thickness and therefore a slightly smaller core volume. Despite the highest test-day temperature of 25.4 °C in the dyno cell, intake air temperature remained at 40 °C on the third run. A maximum of 307.3 BHP and 296.4 lb-ft of torque was achieved. The measurements were repeated, and the test vehicle sensor data was also checked.

The inlet and outlet ports have a diameter of 60 mm. The kit therefore includes the required silicone hoses and mounting hardware for connecting to the original parts. Compared with the original intercooler, the Forge Motorsport version has over 42% greater surface area and over 100% greater internal volume. Gains exceed 10 bhp and 10 lb-ft, depending on the vehicle’s settings and other fitted performance parts.

The intercooler mounts to the original mounting points, so installation requires no cutting of components and the vehicle can be returned to standard condition at any time. The core and end tanks are protected with a black textured anti-corrosion coating, which also contributes to the product’s thermal properties.

Suitable for: Toyota Corolla XII (E21).