Mazda MX-5 Miata NC / RX-8 - 6 Speed Manual Transmission MT6 Strengthening Upgrade Bundle

The Performance Delta Billet Bearing Plate is designed for the Mazda MX-5 NC and RX-8 6-speed MT6 manual transmission, designed to address the well-known weakness in the factory bearing plate Mazda used. The original cast aluminium bearing plate can flex under load, allowing the main and counter shafts to move out of alignment. This movement accelerates gear wear and, in severe cases, can lead to cracking of the factory plate and complete gearbox failure.

This upgrade replaces the factory component with a precision CNC-machined billet bearing retainer plate, dramatically increasing rigidity in this critical area of the gearbox. By maintaining correct shaft alignment under high torque and aggressive driving conditions, it significantly improves long-term gearbox durability for both road and track use.

Installation requires partial gearbox disassembly but does not involve any machining or permanent modification. For best results, installation should follow Mazda’s MT6 transmission overhaul procedures to ensure correct bearing preload and assembly.

Change control system bushes replace the plastic bushes that can easily break on transmissions that see hard use on track.  Made from brass to a tighter tolerance than the factory plastic bush.  These slider blocks are sold as a set of 3 and can be easily installed while the gearbox is out of the car - takes 20 minutes.

This kit replaces the factory plastic bushes (P601-17-481) that are prone to breaking under hard use, especially on track. By upgrading to brass bushes, you ensure greater durability and precision in your transmission control system.

Reverse Change Bush for the Mazda MX-5 NC 6-speed gearbox replaces the factory plastic bushes in the reverse gear change mechanism. Under hard use, particularly on track-driven cars, the original plastic components are prone to wear or failure, leading to imprecise operation or loss of reverse engagement.

Manufactured from brass and machined to tighter tolerances than the OEM parts, this upgrade provides increased durability and improved shift consistency. By eliminating the weak plastic bushes, it offers a more reliable solution for vehicles subjected to aggressive driving conditions.