Improve cooling system reliability and increase resistance to overheating with the Trust / GReddy 13901002 High‑Pressure Radiator Cap (Type‑S). Designed for performance and motorsport use, this cap raises the cooling system’s operating pressure to help prevent coolant boil‑over under high temperature and high load conditions.

The 13901002 is a Type‑S radiator cap with a 1.3 bar (1.3 kg/cm² / 127 kPa) pressure rating. It is manufactured in Japan by TRUST and features a stainless‑steel construction with high‑temperature silicone sealing for consistent pressure control and long service life.

Key Features

• GReddy Type‑S high‑pressure radiator cap
• 1.3 bar opening pressure to raise coolant boiling point
• Improves cooling efficiency during hard driving or track use
• OEM‑style fitment for compatible radiator necks
• Stainless steel cap with silicone seal
• Made in Japan by TRUST

Vehicle Compatibility

The GReddy 13901002 is a Type‑S radiator cap, designed to suit vehicles that use a Type‑S / small‑type radiator neck. Type‑S caps are commonly used on many Japanese performance vehicles, including those fitted with OEM or aftermarket radiators that follow the same neck specification.

Common Applications Include:

• Nissan performance models (Skyline R32 / R33 / R34, Silvia S13 / S14 / S15, 180SX, 350Z, 370Z)
• Mazda performance models (RX‑7 FC3S / FD3S, RX‑8, MX‑5)
• Subaru models using radiator‑mounted caps (Impreza WRX / STI, Legacy)
• Selected Toyota and Mitsubishi models using Type‑S radiator necks

Important: Radiator cap fitment is determined by radiator neck depth and cap type, not vehicle model alone. Some vehicles may use a Type‑N cap instead. Please confirm your existing cap style before purchase.

Why Use a High‑Pressure Radiator Cap?

A high‑pressure radiator cap increases the cooling system’s operating pressure, which raises the boiling point of the coolant. This helps prevent coolant from boiling, foaming, or being pushed into the overflow tank during high‑temperature operation.

• Reduces the risk of overheating under hard driving
• Minimises coolant loss and pressure fluctuation
• Maintains more consistent cooling system performance

Note: High‑pressure radiator caps should only be used on cooling systems in good condition. Aging hoses, radiators, or seals may fail under increased pressure.