Competition Clutch 16+ Honda Civic 1.5T Stage 3 Segmented Ceramic Clutch Steel Flywheel w/ 17lbs
Tuned 1.5 liter turbo Civics make big torque early, and the factory clutch in a 2017-2023 Civic Si is often the first part to give up: rpm flares on a hard pull in third, the pedal bite point creeps upward, or the car starts slipping every time boost comes on. Competition Clutch 8091-STU-2600 is the company's Stage 3 street and strip kit for that car, packaged with its lighter 17 lb steel flywheel. Competition Clutch rates the Stage 3 family at up to 150 percent more torque capacity than stock.
The 1.5T builds torque low in the rev range, which loads the clutch hard every time the turbo spools in a high gear. Stage 3 answers that with a sprung disc faced in segmented ceramic material. Ceramic tolerates far more heat than an organic lining and keeps its grip after repeated launches, and segmenting the facing helps it shed heat and wear evenly. The sprung hub stays in place to absorb driveline shock, which matters on a front-drive car that sees street miles. A performance pressure plate raises clamping force while keeping engagement quick and smooth, in the maker's words.
The STU in the part number is the flywheel option. This version uses a single-piece steel flywheel at about 17 lb; the 8091-ST-2600 sibling pairs the same clutch with a heavier 22 lb steel flywheel. The lighter wheel lets the engine pick up and drop rpm faster between shifts, at the cost of a little more care pulling away from a stop. The kit also includes a throwout bearing and pilot bearing where the application uses them, plus an alignment tool.
Verify that the clutch, not the hydraulics or an oil leak, is the cause. Warm the car, pick fourth gear near 2,500 rpm and go to full throttle; if rpm runs ahead of speed, the clutch is slipping. Check the clutch fluid level and look for a leaking slave cylinder or a pedal that returns slowly. Look for oil at the bellhousing, since a leaking seal will contaminate a new ceramic disc. The slipping diagnosis guide covers the full process. If the car is a lightly modified daily driver, a Stage 2 organic kit such as the 8091-STU-2100 is smoother in traffic.
Competition Clutch catalogs 8091-STU-2600 for the 2017-2023 Honda Civic Si with the 1.5 liter turbo and six-speed manual, which spans the tenth-generation and early eleventh-generation Si. The listing title says 16+, but the 1.5T Civic was sold only with a CVT for 2016, so this is in practice a 2017-and-later kit. The Civic Sport and Sport Touring hatchbacks also offered a manual 1.5T; if you have one of those, send your year and VIN so we can confirm the flywheel and disc match before it ships. It does not fit CVT cars or the Civic Type R.
Clean the crank flange, install the 17 lb steel flywheel with the bolts torqued to the factory spec, and center the disc with the supplied alignment tool; a spare alignment tool kit helps if the included one goes missing. Snug the pressure plate bolts in a crisscross pattern, a turn at a time. Replace the pilot and release bearings if included, inspect the fork pivot, and bleed the clutch hydraulics with fresh fluid of the grade your owner's manual lists. Ceramic discs need a proper break-in before launches; our clutch break-in guide explains the process. If you want the smoothest street manners in a 1.5T upgrade, compare the ACT HC10-HDSS organic street kit.
| Brand | Competition Clutch |
| Part number | 8091-STU-2600 |
| Fits | Competition Clutch 16+ Honda Civic 1.5T Stage 3 Segmented Ceramic Clutch Steel Flywheel w/ 17lbs |
| Type | Clutch Kits - Single |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Competition Clutch lists it for the 2017-2023 Civic Si 1.5L Turbo with the six-speed manual. Sport and Sport Touring hatchback owners should send their VIN so we can confirm before shipping.
Both kits use the same Stage 3 clutch. STU comes with a lighter steel flywheel of about 17 lb, while the 8091-ST-2600 version uses a 22 lb steel flywheel for easier launches.
It can be driven daily, and the sprung hub helps, but the ceramic facing bites harder than an organic disc. If the car spends most of its time in traffic, a Stage 2 organic kit is the more comfortable choice.
Competition Clutch rates its Stage 3 kits at up to 150 percent more torque capacity than the stock clutch.
Use the included release and pilot bearings where supplied, check the fork and pivot for wear, fix any oil leak at the rear main or input seal, and bleed the clutch hydraulics.
