Koyo 12-15 Honda Civic SI 2.4L (MT) Performance Radiator

All-Aluminum Performance Cooling for the 9th Gen Si

The Koyo KH082661 radiator is a direct-fit, high-performance replacement for the factory radiator on the 2012–2015 Honda Civic Si with the 2.4L K24 engine and manual transmission. Designed for street and track use alike, this all-aluminum unit delivers superior cooling capacity, better thermal stability, and proven durability.

Features & Benefits

Upgraded Core for Higher Heat Rejection
The KH series radiator is offered in a high-efficiency 25mm or 48mm V-Core thickness. Both options use a high-density fin design for improved heat dissipation and airflow, keeping coolant temps in check even under aggressive driving or forced induction.

100% Aluminum Construction
Unlike stock radiators with plastic end tanks, the KH082661 is fully constructed from aluminum. The core, end tanks, and fittings are TIG-welded for long-term reliability under pressure and heat.

Track-Tested Durability
Each radiator is pressure-tested during production to ensure leak-free operation. The advanced brazing process eliminates epoxy and maximizes strength throughout the entire assembly.

Bolt-On OEM Fitment
Designed to fit like stock, this unit mounts directly in the factory location and retains compatibility with OEM fans and shrouds. No cutting or fabrication required. (Note: Aftermarket radiator cap required; OEM cap will not fit.)

Improved Cooling Efficiency
Expect 20–35% better cooling capacity over stock, reducing the risk of heat soak during spirited driving, summer traffic, or track sessions.

Fitment Guide

• 2012 Honda Civic Si (2.4L K24, Manual)
• 2013 Honda Civic Si (2.4L K24, Manual)
• 2014 Honda Civic Si (2.4L K24, Manual)
• 2015 Honda Civic Si (2.4L K24, Manual)

Supports both coupe and sedan variants.

Ideal For

• Performance builds or modified engines
• Turbocharged or supercharged setups
• Daily-driven Si models with cooling concerns
• Track or autocross applications needing consistent thermal performance

Why Buy From Us?

• Authorized Koyorad dealer
• Fast, secure shipping
• Expert support from Honda/Acura specialists
• Price-match available upon request
• Same day shipping

Boost your cooling system with the KH082661 Koyorad radiator—built to outperform stock and take the heat, no matter how you drive.

Fitment:

• 2012 Honda Civic Si
• 2013 Honda Civic Si
• 2014 Honda Civic Si
• 2015 Honda Civic Si

Part #: KH082661