Competition Clutch Stage 4 Kit, RSX Civic Si

Competition Clutch Stage 4 Kit, RSX Civic Si

If you're putting real power through a 6-speed K20 and a street clutch is slipping every time you get into boost, the Competition Clutch Stage 4 kit (part 8037-0620) is the solid-hub ceramic 6-paddle answer. It fits the 2002-2006 Acura RSX 2.0L 6-speed and the 2006-2011 Honda Civic Si 2.0L 6-speed. This is the 8037 family, not 8090, and it doesn't fit a TSX or a 5-speed RSX (that's 8036). A flywheel is not included.

What It Is and Why It Works

Stage 4 concentrates friction into six ceramic pucks, so you get more pressure per pad and a disc that keeps its bite at temperatures that glaze an organic. Competition Clutch rates Stage 4 at up to a 250 percent increase in torque capacity over stock and positions it for high-horsepower, forced induction, and race use. The 0620 suffix is the solid-hub (unsprung) disc. Competition Clutch's Stage 4 copy states that 0620 kits are solid hub. Solid hub is harsher than the sprung 8037-1620 kit already in the catalog, because there's no hub spring to take the edge off a launch. Expect chatter, noise, and abrupt engagement. That's the nature of a solid-hub 6-paddle, not a defect.

The kit includes the pressure plate, one ceramic 6-paddle disc, an alignment tool, a pilot bushing, and a throwout bearing. A flywheel is not included. Body lines that mention a billet flywheel or a 230 mm to 250 mm plate are boilerplate. Trust the spec table. Some dealers note you should run an RSX Type-S flywheel with this clutch. Confirm that against your existing flywheel before you order, because this box doesn't include one.

Specs

Fitment

This kit is for 6-speed K20 cars in the 8037 family only. It doesn't fit a 5-speed RSX (that's 8036). It doesn't fit a TSX (that's 8090). It doesn't fit a 2002-2005 Civic Si EP3 unless you've confirmed 8037 against your transmission; Competition Clutch's own body line on this SKU is 2006-2011 Civic Si 2.0L 6-speed. Some dealers also list 02-05 Civic Si and even K24 engines on 8037-0620. Confirm those extras before you order. If you want the complete clutch-and-flywheel 8090 kit that also covers TSX, that's a different family.

What to Know Before You Buy

Be honest about how you drive. A solid-hub ceramic 6-paddle engages like a switch. You'll get chatter creeping through parking lots, a narrow bite, and a left-leg workout in traffic. If the car is a daily Type-S or 8th-gen Si with bolt-ons, you'll be happier with Stage 2 or Stage 3 on this chassis, or with the sprung 8037-1620 if you truly need Stage 4 hold. Buy 8037-0620 when the power level demands a solid hub, not for the part number.

Take the 500-mile break-in seriously. Shift often, stay out of launches, and let the ceramic pads bed into the flywheel and pressure plate. Skip it and you'll chase chatter and blame the kit. The flywheel isn't in the box, so resurface yours or replace it while the transmission is out. Ceramic pucks will eat a glazed surface.

While you're in there, inspect the rear main seal, the slave cylinder, and the clutch master. A tired K-series hydraulic system behind a Stage 4 plate feels worse than the clutch itself. If you're making enough power to need this disc, your factory axles are the next weak link. We'd budget for those while the car is apart.