Competition Clutch 2.4L K Series Stage 2 - Organic Sprung Clutch Kit w/Flywheel
Competition Clutch 8090-ST-2100 is the Stage 2 version of the 8090 clutch-and-flywheel package for Honda's K-series manual cars: the 2002-2006 Acura RSX, 2004-2008 Acura TSX and 2002-2011 Honda Civic Si, plus K24-powered and K-swapped builds. It is the kit to buy when a stock clutch has started slipping after an intake, header and tune, or a worn clutch and a glazed flywheel both need replacing, and you still want a car that is easy to drive in traffic.
When Competition Clutch introduced the 8090-ST design in 2015, it made two changes that matter more than the friction compound. The disc grows from the factory 212 mm to 230 mm, and pressure plate clamp load rises from 1,700 to 2,200 lbf. More friction area and more clamp is how this kit holds more torque without a grabby, on-off engagement. The redesigned release bearing is meant to keep pedal feel consistent from one engagement to the next.
The ST in the part number is the steel flywheel, optimized to 16 lb. Competition Clutch designed it to work with the factory ECU without disabling misfire detection, so the kit needs no ECU reprogramming and keeps the car emissions compliant, which matters on a car that still has to pass inspection. The 2100 suffix marks the Stage 2 street series: a performance pressure plate with a high-torque sprung disc. Our title calls it organic sprung; Competition Clutch's own Stage 2 spec describes the facing as steel-backed Brass Plus, a full-face street material rather than a puck disc, rated for up to an 80 percent increase in torque capacity measured at the wheels, depending on the car.
First make sure it is not hydraulic. A slave cylinder that does not fully retract, or a master holding residual pressure, keeps the plate partly released and feels like slip. Check for leaks and dark fluid at the reservoir. Then do a top-gear roll-on from low rpm at full throttle; if the tach moves ahead of the speedometer, the clutch is slipping. Our slipping diagnosis guide covers the test in detail, and the flare versus slip explainer helps you put what you feel into words. Tired RSX hydraulics can be replaced with this master, slave and braided line kit during the same job.
The catalog lists this kit for the 2002-2006 Acura RSX, 2004-2008 Acura TSX and 2002-2011 Honda Civic Si with a manual transmission. Our title says 2.4L K-series because the kit is a popular choice for K24 engines and K-swaps. On a swap, the crank and transmission you are bolting together decide fitment, not the chassis, so send us your engine code, transmission code and year or VIN and we will confirm before it ships. The 2012-2015 Civic Si is not on the list for this part number. More clutch options are in our rebuild kits and clutch section.
If the car is turbocharged or headed to the track, the Stage 3 8090-ST-2600 uses the same flywheel with a segmented ceramic disc.
Do not reuse the factory flywheel; the 230 mm clutch must run on the matched steel flywheel in the box. Clean both friction faces, bolt the flywheel on with the crank bolts torqued to spec, install the new pilot bushing, then center the disc with the alignment tool and draw the pressure plate down evenly in a star pattern. Bleed the hydraulics with the fluid listed on the reservoir cap. Engine and transmission mounts take extra load with a stronger clutch, so a worn set is worth replacing now; we carry an RSX manual mount kit. Competition Clutch requires a 300-mile break-in for its Stage 2 kits, with normal driving and no hard launches.
| Brand | Competition Clutch |
| Part number | 8090-ST-2100 |
| Fits | Competition Clutch 2.4L K Series Stage 2 - Organic Sprung Clutch Kit w/Flywheel |
| Type | Clutch Kits - Single |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
It is catalogued for the 2002-2006 Acura RSX, 2004-2008 Acura TSX and 2002-2011 Honda Civic Si with a manual transmission, and is commonly used on K24 builds and K-swaps. Send your engine and transmission codes if your car is swapped.
No. The disc is 230 mm, larger than the 212 mm factory clutch, so it has to run on the 16 lb steel flywheel included in the kit.
Competition Clutch designed the flywheel to work with the factory ECU without disabling misfire detection, and says no ECU reprogramming is needed.
Our title follows the catalog label of organic sprung. Competition Clutch's Stage 2 spec describes a sprung disc with steel-backed Brass Plus facings, a full-face street material rather than a puck disc.
Both use the same 230 mm design and 16 lb steel flywheel. The 2100 is the Stage 2 street disc; the 2600 is Stage 3 with a segmented ceramic disc for more torque and harder use.
Competition Clutch requires 300 miles of normal driving for Stage 2 kits before hard launches or track use.
