GREDDY TRUST Aluminium Racing Radiator TW-R for Mazda RX8 (Series 1, 2003-2008)

This Mazda RX8 aluminium radiator from GREDDY TRUST’s TW-R range is the cooling upgrade built specifically for the SE3P Series 1 Renesis. The factory plastic-tank radiator was never intended for sustained heat loads. Whether that means repeated hard laps or Australian summer highway runs, it reaches its limits quickly.

A 40mm full-aluminium core replaces it directly. It cuts heat dissipation by approximately 35% compared to OEM and more than doubles the coolant capacity of the genuine unit.

The two-layer wide-tube design is key. It achieves the flow equivalent of a three-layer structure while keeping pressure loss and weight gain to a minimum. That balance matters for any street-to-circuit RX8 racing radiator build.

GREDDY TW-R Mazda RX8 Aluminium Radiator Features

• Full aluminium construction improves heat dissipation by approximately 35% over OEM. It also eliminates the corrosion and fatigue that eventually degrades factory plastic-tank units.
• The 40mm core thickness delivers more than double the OEM coolant capacity. It also better resists coolant boil-over under sustained load, which matters most at the top of a hard lap or on a long freeway pull in summer.
• A two-layer wide-tube design reduces pressure loss while achieving flow equivalent to a three-layer core. Weight increase stays minimal, keeping the balance right for a street-to-circuit build.
• The OEM fan shroud mounts directly without modification. That clean direct-fit installation means no fabrication, no adapter brackets, and a straightforward swap even in a home garage.
• Finally, a GReddy radiator cap is included. The buffed aluminium tank finish looks as purposeful as it performs, drawing attention whenever the bonnet goes up at a track event. Learn more at GREDDY TRUST.

For rotary enthusiasts heading to track days, the difference shows up where it counts. Coolant temperatures stay stable through repeated hard laps instead of climbing toward the red. The extra reserve capacity the TW-R carries means the cooling system is no longer the limiting factor when the Renesis is working hardest.

Build a complete Series 1 cooling system around this Mazda RX8 aluminium radiator by adding the R-MAGIC Super High Flow Water Pump, which keeps coolant moving efficiently through the larger core, and the BEATRUSH Engine Cooling Under Panel Tray, which channels front airflow directly to the radiator. Round out the Series 1 reliability refresh with the GENUINE MAZDA OEM MAF Sensor, the GENUINE MAZDA OEM Radiator Hose Replacement Set, and the GREDDY TRUST Oil Filter.