Spec Stage 3+ Clutch Kit – BMW 135i / 335i

OVERVIEW

The SPEC Stage 3 PLUS is the flagship stage for a high-powered street or race car that still needs a manageable, friendly engagement. It uses a carbon semi-metallic full-faced material that SPEC rates for unparalleled life, friction co-efficient and drivability in one package. SPEC recommends it for street, drag, drift, autocross, road racing, pulling and rally use.

This is the ratcheting (SAC) version, so it bolts to the OE dual mass flywheel or to an aftermarket billet single mass flywheel with the OE clutch pattern, such as the MFactory SMFW.

SPECS

• Stage 3+ single disc clutch kit
• Torque capacity: 671 ft-lbs
• Friction material: carbon semi-metallic, full-faced
• Pressure plate: SPEC high-clamp, self-ratcheting (SAC) design
• Character: aggressive but streetable engagement; SPEC lists street, drag, road racing, pulling, rally and drift
• Flywheel requirement: runs on the OE dual mass flywheel or an OE-pattern billet single mass flywheel — a SPEC flywheel is optional
• MFactory flywheel option: 21 lb single-piece forged chromoly (SAE 4140), nitride treated, balanced to over 12,000 rpm

PARTS INCLUDED

• Pressure plate
• Clutch disc
• Pilot bearing
• Release (throwout) bearing
• Alignment tool
• Clutch fork
• SPEC clutch kits supplied for use with the OEM dual-mass flywheel include pressure plate, disc, pilot bearing, release bearing, alignment tool and clutch fork.
• SPEC clutch kits supplied for use with a SPEC flywheel include pressure plate, disc, pilot bearing, release bearing and alignment tool.
• When a SPEC flywheel is ordered it ships with pressure-plate-to-flywheel bolts.

TECH RESOURCES

Additional Parts Required

• None. SPEC specifies no additional hardware for this kit — it runs on the OE dual mass flywheel and includes its own pilot bearing, release bearing, alignment tool and clutch fork.
• Optional single mass flywheel upgrade (SAC pattern): SPEC 8-bolt steel SMFW SB53S (2007 – 1/2009), SPEC 8-bolt aluminum SMFW SB53A (2007 – 1/2009), SPEC 6-bolt steel SMFW SB53S-4 (2/2009 on) or SPEC 6-bolt aluminum SMFW SB53A-4 (2/2009 on).
• The MFactory flywheel options on this listing are MFactory parts, not SPEC parts — see the part numbers below.
• MFactory flywheels: on 2011 or newer cars the center section of the flywheel has to be pressed out, because that flywheel covers more than one vehicle generation. To avoid that step, consider the SPEC Stage 3+ SB533F-2 with a SPEC non-SAC single mass flywheel instead.
• If the OE dual mass flywheel is being reused it must be inspected and, where serviceable, resurfaced before the new clutch is fitted.
• Installer-supplied: transmission jack, new flywheel-to-crank bolts and BMW-specification transmission oil if the transmission is drained.

Installation

• SPEC does not publish a downloadable installation PDF for this application — follow the printed installation and break-in instructions supplied with the kit.
• Installation requires removal of the transmission and should be carried out by a qualified technician. Inspect the pilot bearing bore, clutch fork, release-bearing guide sleeve and slave cylinder while the transmission is out.
• Bed the clutch in with light, gradual engagements before applying full load.

Notes

• The current product description quotes SPEC’s Stage 3 6-puck text. SPEC catalogs SB533F as the Stage 3 Plus, which uses the full-faced carbon semi-metallic disc described above. Flywheel bolt pattern also changes with production date: 8-bolt through 1/2009, 6-bolt from 2/2009.
• One variant on this listing is labeled “Most 2/2009-2012 Spec SMFW 8 Bolt”. Cars built from 2/2009 take the 6-bolt flywheel, SB53S-4 — the “8 Bolt” in that label is a typo. Confirm your production date with Speed Logic.
• The 2012–2016 F-Series flywheel option is the SPEC SB55S, which SPEC publishes for its N55 clutch line. SPEC pairs SB55S with the SB553F kit rather than with SB533F — contact Speed Logic to confirm the right combination for an F-chassis car before ordering.
• MFactory's own fitment for both flywheels is stated as 1-Series E8X 135i and 3-Series E9X 335i, manual transmission. MFactory publishes no flywheel for the N55.

PART NUMBER

• Clutch kit: SB533F
• MFactory flywheel, 8-bolt (2006 – 1/2009 production): MF-TRS-09E92
• MFactory flywheel, 6-bolt (2/2009 production on): MF-TRS-09E92A
• SPEC flywheel (SAC pattern), 8-bolt (2007 – 1/2009 production): SB53S steel or SB53A aluminum
• SPEC flywheel (SAC pattern), 6-bolt (2/2009 production on): SB53S-4 steel or SB53A-4 aluminum
• SPEC flywheel (SAC pattern), F-Series N55 2012–2016: SB55S steel or SB55A aluminum — see Notes

VEHICLE APPLICATIONS