Mishimoto Performance Oil Cooler for FK8/FL5 Civic Type R

Mishimoto Performance Oil Cooler Kit - FK8 & FL5 Civic Type R

Track a Civic Type R and oil temperature becomes a real problem, the K20C1 makes serious heat on a hard session, and once the oil gets too hot it stops protecting the engine the way it should, which is how a fun track day turns into a cut-short one. This Mishimoto oil cooler kit adds cooling capacity to keep oil temps in check so you can push the car longer. Available for both the FK8 and FL5 Type R, in black or silver, with a 19-row stacked-plate cooler and a thermostatic setup that won't overcool on the street.

Pick Your Chassis And Finish

The kit is offered for both Type R generations, each in two finishes.

Why An Oil Cooler On A Type R

Worth understanding, because it's about protecting the engine, not just a number.

Engine oil does more than lubricate, it carries heat away from the hottest parts of the engine, and it only works properly within a temperature range. Push a turbocharged, high-revving K20C1 hard on track or a spirited drive, and oil temps climb past that range. Hot oil thins out and protects less, which accelerates wear, and sustained high oil temps are a genuine reliability risk on a hard-driven engine.

An oil cooler adds capacity and sheds heat so the oil stays in its proper range even under hard use. For a Type R that actually sees track time, it's one of the more important things you can do to let the car run hard, lap after lap, without cooking the oil, and both of these kits are thermostatic, so they won't overcool the oil during normal street driving or warm-up.

FK8: Backs Up The Factory Cooler

How the FK8 kit works, since it's specific to that car.

The FK8 is well known for struggling to keep its fluid temperatures in check on track, the K20C1 makes more heat than the factory cooling can handle once you're pushing it or running an aggressive tune. Honda fitted a liquid-to-liquid oil cooler from the factory, which is fine for normal driving but can't keep up on track.

The FK8 kit adds a 19-row air-to-air cooler to supplement the factory liquid cooler (which it retains), using the FK8's aero front bumper to feed it air and drop oil temps by 15°F. Application-specific brackets position it to keep proper airflow through the front wheel well, and it connects with stainless braided lines and -AN fittings. It adds 0.65 quart of oil capacity on top of the cooling.

FL5: More Capacity, Cleaner Integration

How the FL5 kit differs.

The FL5 kit uses the same 19-row stacked-plate cooler, positioned for maximum airflow, and increases total oil capacity 12% over stock, with testing showing oil temps 5°F cooler under demanding driving. It's a clean, thought-out install: a billet oil line separator keeps the lines organized and clear of the belts, black nylon-sheathed stainless lines connect it all, and the horn relocates to an existing bracket location with no wiring changes.

Installation requires minor trimming (or removal) of a factory plastic duct piece, which doesn't affect performance, and the kit includes everything needed for a direct-fit install.

FL5 Owners: Note The Oil Temp Reading

Important to know before installing on an FL5.

The FL5 doesn't have a true factory oil temperature sensor, the oil temp shown on the dash is an inferred value the car calculates, not a direct measurement. Once you add an oil cooler, that inferred reading is no longer accurate, because the actual oil temperature no longer matches what the car assumes.

So if you want accurate oil temps after fitting this on an FL5, you'll want to add a proper oil temperature gauge with its own sensor. It's not a fault of the kit, just a consequence of how the FL5 reports oil temp, and worth planning for if you're the kind of driver who watches the number.

Built Right

Both kits use a robust 19-row stacked-plate core, stainless braced oil lines with -AN fittings for strength and a reliable seal, and a billet thermostatic sandwich plate that routes oil to the cooler only once it's up to temperature. It's complete, direct-fit, and backed by the Mishimoto lifetime warranty.

One install note: it's worth flushing the cooler with a quart of clean oil before installing, standard practice to clear any debris from shipping, and checking all fittings are properly torqued before and after the first few miles.

Fitment

2017-2021 Honda Civic Type R (FK8)
2023-2026 Honda Civic Type R (FL5)

K20C1. Select your chassis and finish (black or silver). See the table above for part numbers.

Who Should Grab This

This is for the FK8 or FL5 Type R owner who tracks the car or drives it hard and wants to keep oil temps in a safe range instead of cutting sessions short or cooking the oil. A 19-row cooler, thermostatic so it won't overcool on the street, more oil capacity, and a clean direct-fit install in black or silver. Pick your chassis and finish, and let the car run hard without worrying about the oil.

Fits: 2017-2021 Civic Type R (FK8) and 2023-2026 Civic Type R (FL5), K20C1. Part numbers: MMOC-CTR-17TBK/TSL (FK8 black/silver), MMOC-CTR-23TBK/TSL (FL5 black/silver). Core: 19-row stacked plate, thermostatic. FK8: air-to-air cooler supplementing the factory liquid cooler, 15°F drop, +0.65 qt. FL5: 12% more oil capacity, 5°F drop, horn relocation, billet line separator. Lines: stainless braided with -AN fittings. FL5 note: dash oil temp reading becomes inaccurate after install (add a gauge for accurate temps). Warranty: Mishimoto lifetime.