Radium Coolant Expansion Tank Kit, Honda Civic Type R (FK8 / FL5)

The Radium Engineering 20-0827 Coolant Expansion Tank Kit is a direct OEM replacement coolant tank for the Honda Civic Type R (FK8 and FL5). CNC machined from 2-piece billet aluminium and anodised for long-term durability, this tank eliminates the failure-prone OEM plastic unit — a known weak point on performance and track-driven Type R builds.

Aluminium's superior thermal conductivity improves heat transfer compared to the factory plastic tank, while the robust metal construction is race-proven and suitable for demanding track applications. The Radium tank directly replaces the OEM unit without any permanent modifications to the vehicle — a specially designed mounting bracket secures to existing threaded holes, and Radium adapter fittings interface directly with the factory coolant lines.

Key Features

• CNC machined 2-piece billet aluminium — eliminates OEM plastic tank failure, race and street proven
• Superior thermal conductivity — aluminium improves heat transfer over the factory plastic unit
• OEM equivalent internal volume — no coolant loss, system capacity unchanged
• Dual chamber internal design — cross-over passages at top and bottom for efficient coolant flow
• Internal swirl deaeration feature — aids in removing air from the cooling system
• Direct OEM replacement — mounts to existing threaded holes, no permanent modifications required
• Factory coolant line compatible — Radium adapter fittings interface directly with OEM lines
• OEM pressure cap reusable — factory 1.3 Bar Honda cap can be retained, or upgrade to a Radium Type-A cap
• All installation hardware included — complete kit, ready to install

Vehicle Fitment

• 2017+ Honda Civic Type R (FK8)
• 2023+ Honda Civic Type R (FL5)

Available Part Numbers

• 20-0827 — Coolant Expansion Tank Kit, Honda Civic Type R FK8 / FL5

Note: The OEM 1.3 Bar Honda pressure cap can be reused. Alternatively, Radium Engineering Type-A pressure caps are available separately in various pressure relief ratings.

Why Radium Engineering?

• ✔ Designed and manufactured in the USA
• ✔ CNC machined billet aluminium — race proven, eliminates OEM plastic failure
• ✔ Dual chamber with swirl deaeration — engineered for performance cooling
• ✔ Trusted by professional motorsport teams and serious enthusiasts worldwide
• ✔ Exclusively distributed in Australia by Coore

Genuine Radium Engineering product. Stocked in Sydney for fast Australian delivery. OEM pressure cap reusable. Radium Type-A pressure caps available separately. Professional installation recommended.