Mishimoto Aluminum Radiator for FL5 Civic Type R/DE5 Integra Type S

Mishimoto Performance Aluminum Radiator (MMRAD-CTR-23) - FL5 Civic Type R & DE5 Integra Type S

The FL5 Type R and DE5 Integra Type S make 315 horsepower from a turbocharged K20C1, and all that power makes heat, more than the factory radiator was built to shed when you drive the car hard. Mishimoto's performance radiator fixes that with a tested result: 17% more heat rejection, which drops outlet coolant temps by an average of 5 to 10 degrees. All-aluminum, direct-fit with no bumper removal, and engineered to use every millimeter of available space for maximum cooling.

A Tested Result, Not Just A Bigger Core

This is what sets this radiator apart, it's measured, not just claimed.

Plenty of radiators advertise a bigger core; what matters is how much more heat it actually rejects. Mishimoto measured this one at a 17% increase in heat rejection over stock, which translates to an average 5 to 10°F drop in outlet temperatures, the temperature of the coolant leaving the radiator and heading back to the engine.

That matters because lower coolant temps mean the ECU is less likely to pull timing to protect the engine, so you keep your power on a hot lap or a hot day, and it gives a built or hard-driven engine more thermal margin. A measured 5-10° drop is a real, usable improvement, not a spec-sheet number that doesn't show up where it counts.

Where The Cooling Gain Comes From

The core is substantially larger and more efficient than stock.

49% more core volume means far more coolant in the radiator and more thermal mass to work with. 31% more external fin area gives more surface for heat to transfer into the air, and 31% more internal tube area gives more surface for heat to move from the coolant into the radiator in the first place. Those increases at every stage are what produce the measured heat-rejection gain.

It's a single-row core, but a thick 40mm strutted-tube one, Mishimoto's design that packs the cooling into a robust core that resists the chassis flex a radiator sees under hard driving, so it won't fatigue or fail where a thinner, unsupported core would stress over time.

Aluminum, Built To Last

The construction is proper performance-radiator build.

It's all-aluminum with precision TIG-welded end tanks, which is stronger and sheds heat better than the factory radiator's plastic tanks, the plastic tanks that crack and become a failure point as a car ages. Aluminum tolerates the heat and pressure of a hard-run cooling system and dissipates heat more efficiently, so the construction itself contributes to the cooling, not just the size.

The Details That Make It Work Better

Two included features that matter.

Foam seals between the radiator and fan shroud ensure the air the fans pull actually goes through the radiator rather than leaking around it, a small detail that meaningfully improves airflow management and real-world cooling. And a magnetic drain plug captures metallic debris circulating in the cooling system, so wear particles collect at the plug instead of cycling through your pump and engine.

Direct Fit, No Bumper Removal

Straightforward to install, which isn't a given on a radiator swap.

This is a plug-and-play direct fit that mounts in the factory location without removing the bumper, a real convenience, since many radiator upgrades require pulling the front end. It reuses the factory fan shroud (with the included foam seals) and works with your stock coolant hoses or the matching Mishimoto silicone hose kit. No fabrication, no cutting, no front-end teardown.

Pair It With The Silicone Hoses

The natural companion for a complete cooling system.

Mishimoto designed this radiator to work alongside their silicone radiator hose kit for these cars. The radiator adds cooling capacity; the silicone hoses replace the factory rubber with four-layer silicone that won't dry, crack, or balloon under the same heat. Together they're the upgraded cooling system Mishimoto built for the FL5 and DE5, and doing both while the cooling system is open is the efficient way to go.

Fitment

2023-2026 Honda Civic Type R (FL5)
2024-2026 Acura Integra Type S (DE5)

K20C1 engine. Part number MMRAD-CTR-23. Direct fit, no bumper removal. Works with stock or Mishimoto silicone hoses.

Who Should Grab This

This is for the FL5 or DE5 owner who tracks the car, tunes it, or just wants more thermal margin on a hot day, and who wants a radiator with a measured result rather than a vague promise. A tested 17% more heat rejection, 5-10° lower outlet temps, 49% more core volume, aluminum that won't crack like the plastic factory tanks, and a true direct fit. Keep your coolant temps in check, pair it with the silicone hoses, and stop losing power to heat.

Fits: 2023-2026 Civic Type R (FL5) and 2024-2026 Integra Type S (DE5), K20C1. Part number: MMRAD-CTR-23. Result: 17% more heat rejection, 5-10°F lower outlet temps. Core: 40mm strutted single-row, 49% more volume, 31% more fin and tube area vs stock. Construction: all-aluminum, TIG-welded end tanks. Includes: magnetic drain plug and fan shroud foam seals. Install: direct fit, no bumper removal; works with stock or Mishimoto silicone hoses. Warranty: Mishimoto lifetime.