Clutch Masters 07-13 Mazda 3 Mazdaspeed 850 PRO Series Twin Disc Clutch w/Steel Flywheel
A Mazdaspeed3 that has outgrown its clutch is easy to spot: the tach swings up in third gear at full boost and the car goes nowhere faster. Clutch Masters part number 10306PTD8RS is the 850 PRO Series twin disc with a steel flywheel for the 2007 through 2013 Mazdaspeed3, aimed at cars with big turbos, ethanol blends or serious tunes that put far more torque through the six-speed than Mazda ever planned. It is a race-grade clutch. Buy it for the power level, not because a stock clutch wore out on a stock car.
From the factory the turbo 2.3-liter MZR made 263 hp and 280 lb-ft, sent to the front wheels through a six-speed manual and a limited-slip differential, and Mazda limited boost in the low gears to control wheelspin. Once a tune removes those limits and the turbo grows, the single-disc clutch is usually the first part to give up. A twin disc places two discs and a floater inside one cover, so the clamp load works on twice the friction area. The 850 is an 8.50 inch (216 mm) unit, larger than the 725 platform, which is why it is the step up when the 725 is not enough.
The PRO redesign is what separates this kit from the older FX850. Clutch Masters swapped the six-post aluminum cover stands for twelve heat-treated 4140 steel stands on a 12-point nut and stud system, and moved to one precision driven hub that engages the input shaft as a single spline. That reduces spline wear, a real concern on a front-drive car that sees hard launches. The PTD8R stage in this part number is Rigid Race, two ceramic discs on the driven hub, and the trailing S marks the steel flywheel. Clutch Masters states that its PRO clutch kits and flywheels are SFI certified.
Run a slip test in a high gear from low rpm with full throttle and watch whether rpm rises faster than speed. Before you condemn the clutch, check the hydraulic side for a leaking slave cylinder or a soft pedal, and look under the bellhousing for engine or gear oil that could be contaminating the disc. Then match the clutch to the car. If you want the twin disc bite with a smaller, lighter package, compare the 725 PRO version for the Mazdaspeed3. If the car is mostly a street car, a single disc such as the ACT XT street sprung kit is easier to live with. Our manual versus automatic repair cost guide helps you plan the labor.
This kit is listed for the 2007 through 2013 Mazdaspeed3, covering both the 2007-2009 first generation and the 2010-2013 second generation, all of which used the turbo 2.3 and the six-speed manual. It does not fit the regular Mazda3 with the 2.0 or 2.5 engines, and it is not the part for the Mazdaspeed6. If your car has had a transmission swap or you are unsure of anything, send us the year and the last 7 of the VIN before ordering. Other clutch and drivetrain parts are in our rebuild kits department.
| Brand | Clutch Masters |
| Part number | 10306PTD8RS |
| Fits | Clutch Masters 07-13 Mazda 3 Mazdaspeed 850 PRO Series Twin Disc Clutch w/Steel Flywheel |
| Vehicle fitment | Mazda 3 Mazdaspeed 850 Pro (2007-2013) |
| Type | Clutch Kits - Multi |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Yes. The listing covers 2007 through 2013, which includes both generations of the Mazdaspeed3.
No. It is for the turbo Mazdaspeed3 only. Non-turbo Mazda3 models use a different clutch.
The 850 PRO is an 8.50 inch twin disc and the 725 PRO is a 7.25 inch twin disc. The bigger diameter gives more friction area for higher power, while the 725 is smaller and lighter.
Yes. Part number 10306PTD8RS includes a steel flywheel, and the twin disc must be used with it.
Expect more engagement noise and a quicker bite than stock. Rigid discs have no springs in the hub, so they transmit more driveline noise. That is normal for this type of clutch.
Clutch Masters calls for at least 500 miles of normal stop-and-go driving, with no full-throttle shifting or compression braking, before full power.
