Spool ZF 8HP70 / 8HP75 / 8HP76 Stage 2 Transmission DIY Kit

Spool Performance products are what we use in our own builds at Racebox. Quality parts, backed by their lifetime warranty.

Spool Performance Stage 2 Transmission Kits for 8HP70, 8HP75, and 8HP76

After over a year of rigorous testing, Spool Performance proudly presents our Stage 2 Transmission Kits for the 8HP70, 8HP75, and 8HP76 series transmissions. Engineered to exceed the limitations of stock components, these kits deliver an exceptional torque capacity of over 1200 ft-lbs. This comprehensive upgrade includes advanced friction materials developed in-house, billet 7075 heat-treated and hard-anodized custom-designed C and E hubs, bespoke pressure plates, apply plates, and increased clutch counts for every clutch pack.

Advanced Hub Design

The C and E clutch hubs in the 8HP series are critical points of failure due to their OEM construction from weak, cast A380 aluminum. These components are prone to shearing or breaking of the lock splines, and the steel clutch plates can dig into the splines, causing hang-ups and burnouts.

Key Upgrades:

• Material: Re-engineered using 7075 series aluminum, one of the highest grades of billet aluminum.
• Treatment: Heat-treated and hard-anodized to enhance strength and surface hardness, providing superior resistance to shear forces and wear from steel disc engagement.
• Design Enhancements: Improved clutch cooling paths, oil evacuation, and increased clutch pack area for optimized performance.

Superior Friction Materials

Our FX-RT frictions, developed in-house, provide significantly higher friction coefficients than OEM materials. These frictions ensure performance and durability without compromising engagement and overall drivability. This development is the culmination of over a year of continuous testing and refinement across multiple platforms.

Ease of Installation

Rebuilding a transmission can be intimidating, so we’ve designed our kits for seamless installation. All clutch packs are pre-clearanced and ready to drop in with custom pressure and apply plates, eliminating guesswork for the installer. Additionally, the kit includes extra steel plates for builders who prefer custom clearance settings.

Features:

• Upgraded Friction Materials: In-house developed for higher friction coefficients and enhanced durability.
• Billet 7075 Hubs: Heat-treated and hard-anodized for superior strength and wear resistance.
• Custom Pressure and Apply Plates: Ensure optimal performance and ease of installation.
• Increased Clutch Counts: Enhanced torque handling capacity for every clutch pack.
• Pre-clearanced Clutch Packs: Ready to install with no need for additional adjustments.
• Extra Steel Plates: Provided for custom clearance settings.

What’s Included

• 7075 Custom Billet E Hub
• E Hub Center Bushing
• 7075 Custom Billet C Hub
• A Clutch Friction & Steels
• A Clutch Pressure Plate
• A Clutch Apply Plate
• B Clutch Friction & Steels
• B Clutch Pressure Plate
• B Clutch Apply Plate
• C Clutch Friction & Steels
• C Clutch Pressure Plate
• D Clutch Friction & Steels
• D Clutch Pressure Plate
• D Clutch Apply Plate
• E Clutch Friction & Steels
• E Clutch Pressure Plate
• Complete Seal kit including Gaskets and O-rings

Recommended Transmission Fluid: AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid (Blue Cap)

The Spool Performance Stage 2 Transmission Kit ensures your 8HP70, 8HP75, and 8HP76 series transmissions are ready to handle increased torque while maintaining reliability and drivability.

Compatibility:

BMW M5 2017–Present - F90

BMW M8 (Coupe) 2019–Present - F92

BMW M8 (Convertible) 2019–Present - F91

BMW M8 (Gran Coupé) 2019–Present - F93

BMW X3 M 2019–Present - F97

BMW X4 M 2019–Present - F98

BMW X5 M 2020–Present - F95

BMW X6 M 2020–Present - F96

BMW M3 2021–Present - G80

BMW M4 (Coupe) 2021–Present - G82

BMW M4 (Convertible) 2021–Present - G83

BMW ALPINA B7 2020–Present - G12

BMW ALPINA B8 Gran Coupé 2021–Present - G16

NOTE: For 8HP70 models only compatible with newer 48 Spline versions.