Single Mass Flywheel for BMW 5 Series E39 (1996-2003)

Adapt an N54 or N55 GS6-53BZ transmission to your M5x/S5x engine to unlock superior torque capacity and optimized gear ratios.

Engineered for the BMW enthusiast who demands more strength and better gear ratios, the Turner Motorsport Transmission Swap Flywheel Kit provides a direct solution for mating a modern N54 or N55 6-speed gearbox to your M20, M5X, or S5X engine. This kit bridges the gap between generations, allowing you to run a high-capacity GS6-53BZ transmission without the typical fabrication nightmares.

The technical core of this kit is our dual-geometry flywheel. By utilizing this specialized design, you can retain your engine-side stock starter while using the factory clutch and throw-out bearing from your donor transmission. This ensures a precise fit and a firm, factory-like shifting feel that can handle significantly more power than older 5-speed setups. To guarantee a fitment, we’ve included a precision drill guide for bellhousing alignment and a universal pilot bearing pin to simplify the installation process.

Features and benefits:

Compatible with the starter from your original motor.
Uses factory clutch and throwout bearing from the donor transmission (GS6-53BZ).
Comes with necessary tools and a provided drill guide to adapt the top transmission mounting holes.
Kit contents:

Swap Flywheel
Pilot bearing input adapter for late N54 and N55 GS6
Drill guide, bit, and hardware.
Flywheel bolts
Optional pilot bearing
Optional clutch
Swap notes:

Fits M20/M50/M52/S50/S52/S54 engines
Needs a custom driveshaft and rear transmission mount. (We used https://www.hdtautoparts.com/driveshafts)
For E46 only: Rear transmission mount can be used from E46 330 6 Speed. Part numbers (22316760531 & 22316760532)
Installation and Support:

Click HERE for installation instructions:

Lightweight flywheels have proven themselves to be a worthwhile performance enhancement. But with the quicker throttle response and horsepower improvement comes one serious drawback: flywheel chatter. Without the dual-mass flywheel's rubber isolators, a lightweight aluminum flywheel has more rattle than stock. ECS has designed this flywheel using chrom-moly steel and it weighs almost ten pounds less than the stock DMF but not as extreme as full aluminum flywheels. The steel helps dampen vibration and noise so you get near-factory refinement and most of the benefits of a lightweight flywheel: quicker throttle response, better reliability, and more power to the wheels. Zero-balanced and SFI 1.1 certified (material and design has been independently burst tested to ensure quality and safety). This flywheel requires the E34 M5 sprung hub clutch kit. Choose below from the flywheel only or a complete kit.

Modern flywheels are built with additional components that are designed to dampen and minimize vibrations from the engine and transmission. Weight has increased and reliability has decreased. With additional weight more energy is required for it to move. A lightweight flywheel does away with the dual mass design and its additional mass so more energy can be diverted to where it counts most - moving the car. The flywheel and clutch is one of the first areas that engine builders address when making the rotating assembly lighter for race engines. The dampening effect is just not needed on cars that are focused on performance. And with a single-mass flywheel the unreliable DMF design is eliminated.

Stock flywheel weight - 25.0lbs
ECS flywheel weight = 16.55lbs

This item fits the following BMWs:
1992-1999 E36 BMW 323is 323ic 325i 325is 325ic 328i 328is 328ic M3
1999-2002 E46 BMW 323i 323ci 325i 325ci 328i 328ci 330i 330ci (5-speed)
1997-2002 Z3 BMW Z3 2.3 Z3 2.5i Z3 2.8 Z3 3.0i M Roadster M Coupe
2003-2005 E85 BMW Z4 2.5i Z4 3.0i (5-speed)