Ford Focus ST Clutch Upgrade: Handling More Boost Without Slipping
The Focus ST's turbocharged 2.0L is easy to tune, and the first thing that tells you the tune worked is usually the clutch letting go: revs flare in third or fourth under boost, the pedal feels different, and the car smells like a hot clutch after a pull. Before you pick a kit, you need to answer two questions: how much torque are you making, and are you keeping the factory dual mass flywheel or converting to a single mass unit?
Shop the Clutch Kits for Your Focus ST
These Focus ST clutch parts are in stock. Check the model years in each title against your car before you order:
- Clutch Masters 13-15 Ford Focus ST 6-Speed FX100 Clutch Kit (07212-HD00-XH) - the heavy-duty street kit.
- Clutch Masters 13-14 Ford Focus ST 2.0L 6-Speed FX350 Clutch Kit, requires Clutch Masters flywheel (07212-HDFF-XH) - the sprung fiber kit for tuned cars.
- Clutch Masters 13-14 Ford Focus ST 2.0L Turbo 6-Speed FX400 8-Puck Lined Ceramic Clutch Kit (07212-HDCL-XH) - the ceramic kit for the most power.
- ACT 16-18 Ford Focus RS / Focus ST Xtreme Clutch Pressure Plate (F024X) - pressure plate only, for builders pairing ACT parts.
More options are in our clutch kits collection, and flywheels are under flexplates and flywheels.
Why the Stock Clutch Gives Up
The factory clutch is built for stock output. Once a tune, intake and downpipe add torque, the clamp load of a stock-style pressure plate is no longer enough, and the disc slips in higher gears under boost. A clutch that slips even a little generates heat quickly, which glazes the disc and can mark the flywheel, so the problem accelerates.
FX100, FX350, FX400: What Each One Is
- Clutch Masters FX100: a heavy-duty pressure plate and steel-backed organic disc, described by the manufacturer as engineered for street-driven cars with only slightly increased pedal pressure and a normal clutch feel, listed at 70% more holding capacity than stock. Clutch Masters positions it for bolt-ons and small nitrous, not forced induction, so on a boosted tuned ST treat it as a replacement-plus kit, not an upgrade for big power.
- Clutch Masters FX350: per Clutch Masters' FX350 page, 110% more holding capacity, aimed at tuned cars with a medium-boost turbo or supercharger, with an estimated 400 ft-lb torque rating. The company says it engages slightly more aggressively than lighter kits and will produce some chatter.
- Clutch Masters FX400: a sprung ceramic disc listed at 170% more holding capacity as an extreme-duty street or race kit. It trades pedal comfort for holding power, with a firmer pedal and more abrupt engagement than organic discs. The 8-puck layout is the less aggressive of the 6- and 8-puck versions.
The Flywheel Decision
The Focus ST uses a dual mass flywheel from the factory. There are two paths:
- Keep the dual mass: ACT sells a Focus ST heavy-duty clutch that is stated to be compatible with the OE dual mass flywheel; the retailer listing gives a 33% clamp force increase and a 445 ft-lb torque rating, with a moderate, consistent pedal feel. This keeps the smooth factory behavior.
- Convert to single mass: Clutch Masters' Focus ST steel flywheel (18 lb steel, with a 24 lb steel and a 9 lb aluminum version also offered) replaces the dual mass flywheel for the 2013-2017 2.0L 6-speed. The manufacturer is explicit that it is a conversion flywheel that only works with a Clutch Masters clutch kit, not the OE clutch or other aftermarket kits. That is why the FX350 listing above says it requires a Clutch Masters flywheel.
Single mass flywheels rev quicker but generally add more drivetrain noise at low rpm. For a daily-driven ST, the dual mass option with a strong clutch is usually the quieter choice. Our write-up on single mass vs dual mass flywheels covers the same trade-off.
Match the Clutch to Your Power
- Stock to light tune: a replacement or heavy-duty street kit such as the FX100 or an ACT heavy-duty clutch.
- Stage 2 power with daily use: a kit rated near or above your tuned torque with some margin, such as the FX350 (estimated 400 ft-lb) or the ACT clutch rated to 445 ft-lb.
- Track or high boost: the ceramic FX400 class, accepting the firmer pedal.
Always leave margin above your dyno torque figure, since a clutch rated right at your peak torque will slip as it wears.
Replace While the Transmission Is Out
- Flywheel: resurface or replace it, per our guide on when to replace the flywheel during a clutch job.
- Release bearing and pilot bearing (included in the Clutch Masters kits where applicable).
- Rear main seal and transmission input seal if weeping.
- Clutch hydraulics if the pedal is soft: clutch hydraulics.
Cost and Effort
This is a transmission-out job on a front-wheel-drive car: plan a full day with the right tools, and longer if you are converting the flywheel. Doing the flywheel, seals and hydraulics at the same time costs far less than a second teardown.
Frequently Asked Questions
Do I need to replace the dual mass flywheel on a Focus ST?
Not necessarily. ACT lists a heavy-duty clutch compatible with the OE dual mass flywheel. If you choose a Clutch Masters single-disc kit with its steel flywheel, it is a conversion that requires Clutch Masters parts together.
Which clutch handles a tuned Focus ST?
Clutch Masters estimates 400 ft-lb for the FX350 and ACT rates its Focus ST heavy-duty clutch at 445 ft-lb. Pick one with margin above your tuned torque.
Will a stronger clutch feel worse every day?
Organic and Kevlar kits stay fairly smooth, while sprung ceramic kits such as the FX400 have firmer pedal effort and more abrupt engagement.