PMC Motorsport adapter plate / conversion kit / clutch kit Honda K20 K24 – 6-speed manual BMW M57N2 ZF GS6-53DZ HGU HGK 325d 330d – 240 mm / 9.45"

Adapter plate designed to mate (swap / conversion) the Honda K20 / K24 engine with the ZF GS6-53DZ HGU / HGK 6-speed manual gearbox found in BMW M57N2 applications (E9x 325d / 330d), as well as the GS6X53DZ HGW / HGL variant from xDrive models (E9x 330xd). The ideal solution for 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. Flywheel designed for 240 mm pressure plates (GS5-39DZ / GS6-53DZ / BZ BMW OE). Adapter thickness: 20 mm (0.78").

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 matched to the chosen gearbox – in this kit, a flywheel designed for a BMW 240 mm pressure plate paired with the ZF GS6-53DZ HGU / HGK transmission. 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. The release bearing and clutch fork are retained from your gearbox – install the clutch fork on the lower release bearing position (if using a two-position release bearing), and replace the factory clutch pivot pin with the custom pivot pin included in the kit. A 240 mm clutch disc with the appropriate spline profile for your gearbox must be used. The original Honda K20 / K24 starter motor (OE, not included in the kit) must be used.

Frequently Asked Questions

Which engines is this adapter 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 adapter fit?

With the 6-speed manual ZF GS6-53DZ gearbox from BMW M57N2 applications (E90 / E91 / E92 325d and 330d) in versions HGU (THGU) and HGK (THGK), as well as the xDrive variants GS6X53DZ HGW (THGW) and HGL (THGL) – E9x 330xd. Input shaft spline is 32.5x35-26N.

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, 240 mm pressure plate and clutch disc with 32.5x35-26N splines, 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 pressure plate fits the PMC flywheel?

A 240 mm (9.45") BMW OE type pressure plate – from BMW M57 / M57N / M57N2 (including the factory GS6-53DZ pressure plate) / N54 / B58 / E46 M3 or Sachs Performance 883082.001243, as well as Sachs XTend 3000 951 952 (M57N / M57N2) and Sachs XTend 3000 951 949 (N54 / N55). Aftermarket ACT / Spec / Tanaci clutches are also commonly used – the custom pressure plate must fit a BMW OE flywheel (M57 / M57N / M57N2 / N54 / B58). Use a clutch disc with the matching spline pattern, dedicated release bearing kit, and slave cylinder for your transmission.

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, custom PMC Motorsport flywheel with replaceable friction insert, pressure plate mounting bolts, and a custom clutch pivot pin – replacement for BMW OE 21 51 1 223 328. Clutch kit, release bearing, clutch fork, and slave cylinder are not included – they must be matched to your gearbox setup.

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

Yes. Every single component of the kit is available separately.

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.