ACT 15-18 Subaru WRX HD/Perf Street Sprung Clutch Kit (Will Not Fit Vin J-806877)
The ACT SB5-HDSS is a street clutch kit for the 2015 to 2018 Subaru WRX with the 2.0L turbo FA20 and six-speed manual. It is the kit owners reach for when the factory clutch starts slipping after a tune, an intake and downpipe, or simply high mileage, but the car still has to be pleasant in traffic. One important limit up front: Subaru changed to a larger clutch partway through the 2018 model year, and this kit does not fit cars from VIN J-806877 onward.
SB5-HDSS pairs ACT's Heavy Duty pressure plate with its Performance Street sprung organic disc. ACT rates the combination at 420 ft-lb at the crank, 32 percent more than the original clutch. The disc is 228 mm (9 in) on a 1 in input spline, and the copper-rich organic lining is steel-backed for burst strength while keeping a smooth, predictable take-up. Because the hub is sprung, it soaks up the driveline shock that a solid-hub race disc would pass straight into the gearbox.
The kit is complete except for the flywheel: SB014 Heavy Duty pressure plate, 3000502 sprung street disc, RB846 release bearing, PB1004 pilot bearing and the AT90 alignment tool. ACT describes the feel as light to moderate pedal effort with smooth, positive engagement, and expects Heavy Duty plates to raise pedal effort roughly 15 to 40 percent over stock.
A turbo car can feel flat because of boost leaks or a failing wastegate, so prove slip first. In fourth gear at low rpm, roll into full throttle and watch the tach against the speedometer: if rpm jumps and speed lags, the friction is slipping. Also check the clutch fluid level and look for oil at the bellhousing seam, which can mean a rear main or transmission input seal is contaminating the disc. Our slipping diagnosis guide walks through separating clutch slip from other drivability faults, and the flare versus slip article explains what each one feels like from the seat.
Our listing covers the 2015 to 2018 WRX (not the STI) with the six-speed manual, built before VIN J-806877. ACT's application chart also lists this part number for earlier 2.5L turbo cars, including the 2005 to 2014 Impreza WRX, Legacy GT, Outback XT, Forester XT and the 2006 Saab 9-2X Aero, which use the same 228 mm clutch size. Late 2018 and newer WRX cars moved to 240 mm clutch parts and need a different kit. Read the last six characters of your VIN, or send us the full VIN and year, and we will confirm before it ships. More options are in our rebuild kits category.
If you plan to run big power or track days and can live with a sharper engagement, compare the SB5-HDG6 6-pad race kit, which uses the same plate with a ceramic disc.
| Brand | ACT |
| Part number | SB5-HDSS |
| Fits | ACT 15-18 Subaru WRX HD/Perf Street Sprung Clutch Kit (Will Not Fit Vin J-806877) |
| Vehicle fitment | Subaru Wrx Hd/Perf (2015-2018) |
| Type | Clutch Kits - Single |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Only if the car was built before VIN J-806877. Subaru switched to a 240 mm clutch after that point and ACT states this kit will not fit those cars. Send us your VIN and we will check it.
No. It includes the pressure plate, sprung organic disc, release bearing, pilot bearing and alignment tool. You can resurface the stock flywheel or add an ACT XACT flywheel such as the 600475 Prolite.
ACT rates the SB5-HDSS at 420 ft-lb measured at the crank, which is 32 percent over the factory clutch. That covers most bolt-on and tuned FA20 street cars.
ACT expects Heavy Duty pressure plates to increase pedal effort by roughly 15 to 40 percent depending on the car. Most WRX owners describe it as noticeably firmer but fine for daily driving.
The WRX clutch hydraulics run on brake fluid. Bleed the system with fresh DOT 3 or DOT 4 after the install and check for a firm, consistent pedal.
Yes. ACT recommends 300 to 500 miles of mild, stop-and-go style driving on organic street discs before launches or hard pulls so the friction surfaces seat without glazing.
