Competition Clutch Stage 4 Clutch Kit | K20 RSX, Civic Si

Competition Clutch Stage 4 Clutch Kit | K20 RSX, Civic Si

If you're pushing your 2002-2006 Acura RSX or 2002-2011 Honda Civic Si hard, the Competition Clutch Stage 4 (8037-1620) is the "I'm done with stock" move. Turbo, supercharger, nitrous, or a rowdy street and strip K20 build: this is the clutch you bolt in when you're done slipping through third and fourth. One thing up front so nobody's surprised at the box: the flywheel is not included, so plan on a new or freshly resurfaced flywheel in the same job.

What the Stage 4 Actually Is

The disc is a six-puck, torque-sprung setup with ceramic buttons, so it grabs hard and survives heat. Competition Clutch rates the Stage 4 at up to 250% over stock torque capacity, around 400 lb-ft at the wheels per the manufacturer, with roughly 1,700 lbs of pressure plate load behind it. Engagement is firm and direct, but the sprung hub damps the shock loads that an unsprung "on/off" disc feeds straight into your transmission, which is the difference between a race clutch you can drive to the track and one that lives on a trailer.

The kit comes as a full package: performance pressure plate, six-puck ceramic sprung disc, throwout bearing (where applicable), pilot bearing or bushing (where applicable), and an alignment tool. Everything except the flywheel, so you're not mixing random parts to complete the install.

Key Features

• Fits K20 engines in the 2002-2006 Acura RSX (K20A3 5-speed and K20A2/K20Z1 Type-S 6-speed) and 2002-2011 Civic Si (EP3 K20A3, FG2/FA5 K20Z3)
• Six-puck torque-sprung ceramic disc: aggressive bite with more streetable manners than an unsprung puck
• Up to 250% increase in torque capacity, approx. 400 lb-ft at the wheels (per manufacturer)
• 1,700 lb pressure plate load (per manufacturer)
• Includes throwout bearing, pilot bearing/bushing, and alignment tool
• Flywheel NOT included: pair it with a new flywheel or have yours resurfaced
• Recommended 300-mile street break-in for the most consistent engagement

Fitment

K-series manual transmissions only. If you're K-swapped in an older chassis, this kit works with your K20 and its transmission; the chassis doesn't matter to the clutch.

What to Know Before You Buy

Sort the flywheel before the transmission comes out. A fresh ceramic disc on a heat-checked, glazed flywheel is how you get chatter and hot spots that no break-in will cure. Resurface your stock flywheel or grab a new one in the same order, and while everything's apart, look at the clutch master and slave cylinders, because a 1,700 lb pressure plate will find the weak spot in tired hydraulics.

Then break it in like you mean it. For the first 300 to 500 miles, stay out of full-throttle launches and high-RPM clutch dumps. Shift often, use light to moderate throttle, and let the disc seat into the flywheel and pressure plate. That's what gives you stable engagement and long life instead of hot spots and chatter. And be honest about the car: a six-puck ceramic disc on a bolt-on daily is more clutch than you need, and a Stage 2 or 3 will be far friendlier in traffic. This one is for builds that actually make the power. If you're unsure about setup or break-in, reach out and we'll walk you through what's worked on our own K20 builds.