PRODUCT DETAILS
HKS S Type Oil Cooler Kit (15004-AH104) - 2017-2021 Civic Type R
Take an FK8 on track and you'll eventually meet the fail-safe. Oil and water temperatures climb, the ECU pulls power to protect the engine, and your session is over whether you were ready or not. The factory water-cooled oil cooler simply isn't enough for sustained circuit use, and this HKS kit is the air-cooled answer.
Why The Factory Setup Runs Out
Honda asks a lot of two liters. The K20C makes 320ps from a small displacement, which means a lot of heat concentrated in a compact package.
The factory oil cooler is water-cooled, which ties oil temperature to coolant temperature. That works on the street where neither gets extreme. On track it becomes a problem, because the same cooling system is now fighting both, and when one climbs the other follows.
Once temps cross the threshold, the ECU protects itself by pulling power. That's the fail-safe, and it's the reason a lot of FK8 owners find their lap times getting worse as a session goes on rather than better.
Air Cooling Breaks The Link
Moving to an air-cooled oil cooler separates oil temperature from coolant temperature, and that's the fundamental change.
Oil now rejects heat to ambient air through its own dedicated core rather than dumping it into the coolant. That helps twice: oil temperature comes down directly, and coolant temperature comes down because it's no longer carrying the oil's heat load as well.
The practical result is a car that holds its power through a full session rather than tapering off after a few laps.
What Makes This Kit Work
Three things beyond the core itself.
The 9-layer core is a newly developed 48mm wide design at 200 x 122.5 x 48mm, sized specifically for this application rather than adapted from a universal part.
The aluminum air guide is what makes the core effective. A cooler only works if air actually passes through it, and on a car where every bit of front-end airflow is already spoken for, ducting air deliberately to the core is the difference between a cooler that works and one that's just sitting there.
The built-in thermostat prevents overcooling. That matters more than people expect, since oil that never reaches operating temperature is its own problem, particularly on a street-driven car in cold weather. The thermostat means the cooler engages when it's needed rather than running all the time.
They Thought About Noise
A detail worth mentioning because it's the kind of thing that gets skipped.
Adding an oil cooler means adding lines, and lines transmit engine pulsation into the cabin as a low drone. HKS uses a high-pressure resistant stainless mesh hose with an insulator specifically to keep that out of the interior.
On a car you drive to the track rather than trailer to it, that's the difference between a modification you enjoy and one you notice on every highway mile.
Plan For Some Modification
Be realistic about the install before you order.
HKS puts this at roughly four hours, and it requires modification to the back of the bumper, the inner fender, and the brake duct.
Nothing dramatic, and nothing that changes the car's appearance from outside, but it's cutting rather than bolting. If you're not comfortable with that, factor in a shop. And if the car is a lease or you're planning to return it to stock, know that those modifications are permanent.
Specifications
- Product code: 15004-AH104
- Core size: 200 x 122.5 x 48mm
- Core: 9-layer, 48mm wide
- Air guide: aluminum, application specific
- Thermostat: built in
- Hose: high-pressure resistant stainless mesh with insulator
- Install time: approximately 4 hours
- Weight: 7kg
Fitment
2017-2021 Honda Civic Type R (FK8), K20C
Who Should Run This
This is for the FK8 owner who takes the car to track days and has met the fail-safe, or who's planning to and would rather not. Sustained circuit driving is exactly where the factory cooling falls short, and this is the fix rather than a workaround. Budget the four hours, accept the modifications, and get a car that holds its power for a full session.
Fits: 2017-2021 Honda Civic Type R (FK8). Product code: 15004-AH104. Core: 9-layer, 200 x 122.5 x 48mm. Includes: aluminum air guide, stainless mesh hose with insulator, built-in thermostat. Install: approximately 4 hours, requires modification to bumper rear, inner fender, and brake duct. Weight: 7kg.
2017-2021 Honda Civic Type R