PMC Motorsport Race Stage 2 – clutch kit Honda K20 K24 – 6-speed manual BMW M57N2 ZF GS6-53DZ HGU HGK 325d 330d – 184 mm / 7.25" STEP – Tilton OT-II Cerametallic 66-302 HGG Twin disc

Complete Race Stage 2 clutch kit designed to mate (swap / conversion) the Honda K20 / K24 engine with the ZF GS6-53DZ HGU / HGK 6-speed manual gearbox from BMW M57N2 diesel applications (E90 / E91 / E92 / E93 325d and 330d). The kit includes an aluminum gearbox adapter plate, a PMC Motorsport Ultralight Race 184 mm (7.25") STEP-type flywheel, and a high-performance Tilton twin-disc clutch – OT-II Cerametallic 7.25" 66-302 HGG pressure plate and two Tilton 64185-8-VV-55 sintered clutch discs. Designed for drifting, amateur, and professional motorsport.

Planning a Honda K20 / K24 engine swap into your BMW (E30, E36, E46, E34, E39, E90, E91, E92, E60, E61, E81, E82, E87)? Our adapter is a reliable solution. Replace the automatic transmission with a BMW manual gearbox and unlock new performance potential.

PMC Motorsport adapters not only enable automatic-to-manual conversions in Honda K20 / K24 powered vehicles, but also provide ideal solutions for Honda K-series swaps into BMW chassis and other platforms such as Nissan (S13, S14, S15, PS13) or Mazda RX-7 / RX-8.

The aluminum gearbox adapter plate is engineered to simplify gearbox installation as much as possible, eliminating radical modifications like cutting the bellhousing – only preparing the starter motor opening is required. Custom flywheels dedicated to PMC Motorsport adapters are manufactured from aluminum with a replaceable friction surface, fully inspected and dynamically balanced before dispatch. The Ultralight Race flywheel is designed for 184 mm (7.25") STEP-type clutches, matched in this kit with the Tilton OT-II Cerametallic 7.25" 66-302 HGG pressure plate and two Tilton 64185-8-VV-55 sintered discs featuring 32.5x35-26N splines for the GS6-53DZ transmission. Adapter thickness: 20 mm (0.78"). The small clutch diameter and low rotating mass ensure lightning-fast throttle response.

PMC Motorsport gearbox adapters are synonymous with precision and premium quality. The engineering process incorporates 3D scanning and CMM measuring arm inspection to deliver a flawless fit. High-precision CNC machining ensures perfect engine-to-gearbox concentricity, which is crucial for the longevity of the entire drivetrain.

Additional Information

Installation Manual

The gearbox adapter plate requires the use of a custom PMC Motorsport flywheel – in this kit, it is the Ultralight Race 184 mm (7.25") STEP-type flywheel matched to the ZF GS6-53DZ gearbox. Installing the flywheel requires Honda OE 90011-RBD-000 crankshaft bolts (not included in the kit), torqued to 118 Nm (87 lb⋅ft) using threadlocker. Mount the clutch fork on the lower release bearing position (if using a two-position release bearing), and shorten the gearbox guide tube (BMW OE 23 11 7 501 714) according to the diagrams below. The original Honda K20 / K24 starter motor (OE, not included in the kit) must be used.

Frequently Asked Questions

Which engines is this kit compatible with?

With Honda K20 engines (K20A, K20A1, K20A2, K20A3, K20A4, K20A6, K20Z1, K20Z2, K20Z3, K20Z4) and Honda K24 engines (K24A1, K24A2, K24A3, K24A4, K24A8, K24Z1, K24Z2, K24Z3, K24Z4, K24Z5, K24Z6, K24Z7).

Which transmissions does this kit fit?

With the 6-speed manual ZF GS6-53DZ gearbox from BMW M57N2 diesel applications in versions HGU (THGU) and HGK (THGK) – E90 / E91 / E92 / E93 325d and 330d.

Do I need to cut the gearbox bellhousing?

No. The adapter plate is designed specifically to avoid cutting the bellhousing – only preparing an opening for the starter motor is required.

Which additional parts do I need to complete the installation?

Honda OE 90011-RBD-000 crankshaft bolts, release bearing, clutch fork, clutch slave cylinder matched to your gearbox, and an original Honda K20 / K24 starter motor (OE). These parts are not included in the kit.

Which clutch is included in the kit?

A Tilton 184 mm (7.25") STEP-type twin-disc racing clutch: Tilton OT-II Cerametallic Pressure Plate 7.25" 66-302 HGG and two sintered Tilton 64185-8-VV-55 clutch discs with 32.5x35-26N (26 splines) profile for the ZF GS6-53DZ gearbox.

Does the gearbox require any modifications?

Yes. When installing a 184 mm clutch assembly, the gearbox guide tube must be shortened. Refer to the diagrams in the "Installation Manual" section for details.

Is this kit suitable for daily street driving?

No. The Race Stage 2 kit with a rigid Tilton twin-disc racing clutch is engineered strictly for motorsport and drifting applications. For street and daily driven cars, we recommend our adapter version paired with a flywheel designed for standard BMW 240 mm pressure plates.

Which starter motor should be used?

The original factory Honda K20 / K24 (OE) starter motor. The starter is not included in the kit.

Is this adapter compatible with the ZF 8HP automatic transmission?

Yes. The PMC Motorsport adapter plate is universal and compatible with most BMW transmissions (applies to adapter plates manufactured after 2022). When converting to a ZF 8HP automatic transmission, the manual flywheel is replaced by a PMC Motorsport 8HP torque converter adapter.

What is included in the kit?

Aluminum gearbox adapter plate with mounting hardware, PMC Motorsport Ultralight Race 184 mm custom flywheel with replaceable friction insert, pressure plate mounting bolts, Tilton OT-II Cerametallic 7.25" 66-302 HGG pressure plate, and two Tilton 64185-8-VV-55 clutch discs.

Can I purchase only the adapter plate or only the flywheel?

Yes. Every single component of the kit is available separately – including the adapter plate paired with the Ultralight Race 184 mm STEP flywheel without the clutch assembly.

Does the price include customs duty for shipments outside the European Union?

No. Product prices and shipping quotes do not include import customs duties, taxes, or brokerage fees applicable in the destination country.

Can I buy with 0% VAT?

Yes, if you are a B2B customer outside Poland with an active European VAT number (verified via VIES) or if the order is shipped outside the EU.

Is the included manual sufficient to complete the entire conversion?

The manual provides the steps necessary to mate the engine and transmission outside the vehicle. Depending on the chassis, custom work may be required (mounts, crossmember, firewall or tunnel modification, driveshaft length). Professional installation is strongly advised.

Please note that a lightweight single-mass flywheel provides unmatched throttle response and engine acceleration by eliminating standard damping elements. This creates a direct drivetrain connection, which may result in natural and audible transmission gear rattle/gear chatter. This is an expected and characteristic trait of motorsport drivetrains resulting from the rigid mechanical coupling.