IAG Triple Pass Street Series 42mm Radiator for 2015-21 Subaru WRX

The IAG Triple Pass Street Series 42mm Radiator is a high-performance aluminum radiator designed specifically for 2015–2021 Subaru WRX models. Engineered to deliver improved cooling over the OEM radiator, this lightweight upgrade is a solid choice for heavy-use applications and performance-modified engines that generate more heat. Its all-aluminum construction offers excellent heat dissipation, helping maintain stable engine temperatures even under demanding conditions. The IAG Triple Pass Street Series 42mm Radiator is an ideal solution for increased cooling efficiency and long-term reliability.

The IAG Triple Pass Street Series 42mm Radiator features an advanced 3-pass design, using internal baffles within the end tanks to route coolant through the radiator three times from inlet to outlet. Unlike the OEM radiator’s single-pass layout, this design keeps coolant inside the core longer, resulting in a significant increase in cooling efficiency. On average, the 3-pass configuration delivers a 10–20% improvement in cooling performance over stock, providing your engine with better thermal management even during high-performance use.

The IAG Triple Pass Street Series 42mm Radiator is built from lightweight and durable aluminum, making it less likely to crack or bend even under high temperatures. Aluminum's superior heat conductivity and rapid absorption properties allow the hot coolant to cool more quickly as it passes through the radiator tubes. Aluminum also resists corrosion, contributing to a long lifespan and reliable performance. Designed to handle the demands of high-performance use, the IAG Triple Pass Street Series 42mm Radiator delivers efficient cooling with lasting durability.

The IAG Triple Pass Street Series 42mm Radiator uses a relocated upper inlet and requires the included IAG 4-Ply Silicone upper and lower radiator hoses for proper fitment. It features a 42mm (1.654") core and is designed to work seamlessly with OEM radiator fans using the original mounting positions. A welded -6 AN fitting is included on the radiator, and a -6 AN cap is provided for applications that do not use an expansion tank, allowing the radiator to function with a standard OEM-style cooling system.