KOYO RX7 N-Flow Aluminium Radiator - Suits Mazda RX7  FD Series 6/7/8 '92-02 Manual

Rotary Engines Don’t Forgive Overheating

The 13B-REW runs hotter and less forgivingly than a piston engine, and a factory plastic-tank radiator on a car this age was never built for spirited driving decades on. Push it hard on a warm day and rising coolant temps show up fast, followed by fading power and, eventually, apex seal damage.

A Cooling System Built for Real Punishment

Koyo's 48mm N-Flo core is engineered with optimised fin density and tube design to move more heat out of the system, backed by a full-aluminium, TIG-welded build that shrugs off the vibration and heat-cycling that kills OEM plastic tanks over time. Every unit is pressure-tested before it leaves the factory.

Key Features

• All-aluminium construction with TIG-welded tanks for maximum durability
• 48mm core for increased cooling capacity over the factory unit
• Optimised fin density and tube design for efficient heat transfer
• Direct-fit design | uses factory mounting points and fan shroud, no modifications required
• Compatible with standard radiator caps and coolant hoses (unless otherwise specified)
• Pressure-tested for reliability under sustained high load and temperature
• Ideal foundation for further performance upgrades, including higher boost levels 

Important Fitment Notes for 1998+ FD3S Models

Late 1998–2002 Series 7 and Series 8 models use a factory plastic fan shroud with slightly revised mounting-tab positions. This radiator is pre-drilled for the earlier 1993–1995 shroud configuration, so one or two fan shroud bolt holes may not align perfectly on a later car. In most cases, the shroud can be secured by carefully slotting the plastic mounting tabs or by using suitable zip ties or custom brackets to secure the fan assembly.

Some late-model variants, including certain Spirit R models, may also have slightly different angles at the front engine covers and water-pump necks. Standard aftermarket silicone radiator hoses based on the 1993–1995 layout will usually stretch or bend into position, but trimming the hose length may be required to prevent kinks in a 2002 engine bay. Check hose routing and clearance carefully before final tightening.