Skip to product information
5 left
Koyo 93-95 Mazda RX-7 1.3L Turbo Radiator
$506.00
Koyorad HH060644 Racing All Aluminum Radiator
The Koyorad HH060644 is the "Standard" high-performance variant of the 48mm Hyper Core series for the 1993–1995 Mazda RX-7 (FD3S).
While it looks identical to the "N" version from the outside, the key difference is the internal flow path. This model uses a Single-Pass (Vertical Flow) design, which offers less flow restriction than the dual-pass version, making it the preferred choice for specific high-flow water pump setups or builds where minimizing cooling system backpressure is the priority.
Key Specifications:
- Core Series: HH Series "Hyper Core"
- Design: Single-Pass (Standard Flow).
- Core Thickness: 48mm (thickest "drop-in" core available from Koyo).
-
Construction: Mirror-polished aircraft-grade aluminum, hand-assembled, and TIG-welded.
Notable Features:
- High Fin Density: Uses Koyo's signature ultra-high fin pitch to maximize surface area for heat exchange within the 48mm core.
- Nocolok Brazing: Advanced furnace brazing process that bonds the tubes and fins without the need for corrosive flux, ensuring a long-lasting, leak-free life.
- OEM Integration: Bolts directly to factory fan shrouds and uses stock hose locations. No "shaving" or custom brackets required.
- Sensor Port: Pre-tapped 1/8" NPT port for water temperature sensors.
Critical Notes:
- Radiator Cap: Requires a Koyo SKC-13 (or equivalent 1.3 bar deep-plunger cap). The stock Mazda cap will not seal.
- Transmission: Optimized for Manual Transmission (MT). Not compatible with the stock automatic transmission cooler lines
HH060644 vs. HH060644N Click here for the "N" Model
| Feature | HH060644 (Standard) | HH060644N (N-Flo) |
| Flow Path | Single Pass | Dual Pass (Double Flow) |
| Cooling | High Efficiency | Maximum Efficiency (+35%) |
| Pressure Drop | Minimal | Moderate |
| Best For | High-flow water pumps | Extreme street/track heat |
This Part Fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 1993-1995 | Mazda | RX-7 | Base |
| 1993 | Mazda | RX-7 | R1 |
| 1994-1995 | Mazda | RX-7 | R2 |
| 1993-1995 | Mazda | RX-7 | Touring |