MINI 8HP Transmission Harness
MaxxECU MINI + 8HP Transmission Harness Bundle
Developed and tested on the Magnussen Superchargers SEMA car, the Ragebait! See [HERE]
Overview
Upgrade to an 8HP transmission easily with this 8HP Harness designed for use with the MaxxECU MINI. This system combines the compact yet powerful MaxxECU MINI Engine Control Unit with a custom Seems Legit Garage wiring harness to seamlessly manage the renowned ZF 8-speed (8HP) automatic transmission. Whether you're swapping an 8HP into a project car or enhancing your race vehicle’s gearbox control, this bundle provides an easy, reliable way to get your wheels turning.
Harness Reference Sheet [HERE]
Advanced 8HP Gearbox Control
The MINI may be a small ECU, but it packs the full transmission-control capabilities of its bigger siblings (like the RACE) at an affordable price. It runs the same powerful MTune software and 8HP control strategy as larger MaxxECU's, giving you robust features and tuning flexibility. We’ve proven its performance in our own LS-powered race car – delivering quick, crisp shifts and rock-solid reliability under extreme conditions.
Key Transmission Control Features Include:
Full Gen1 8HP Support: Convert and control any first-generation ZF 8HP45, 8HP70, or 8HP90 transmission with no internal TCU modifications needed (Only a flash). The MaxxECU communicates with the stock 8HP TCU via CAN, so no custom valve body wiring or soldering is required.
Customizable Shift Strategies: Enjoy complete control over shift scheduling. You can set shift points anywhere from 1500 to 9000 RPM to suit your engine and driving style. Multiple drive modes from comfort to race are supported, and you can fine-tune clutch pressures and shift timing on the software.
Drag Race Features: Launch harder with the built-in transbrake function, which locks the transmission for standing starts. A bump feature is included to allow inching forward in staging, making it ideal for drag racing. Uniquely, MaxxECU enables transbrake usage in both Drive and Manual modes and even lets you launch in first or second gear as needed.
Flexible Shifter Options: Control gear shifts your way – the system works with OEM BMW or Dodge shifters as well as aftermarket sequential shifters. You can even use a custom keypad or paddle shifters via the ECU’s shift-emulation mode for a truly bespoke setup.
Intelligent Performance Aids: The MaxxECU 8HP strategy includes features like kickdown on demand for lightning-fast downshifts (great for overtaking) and a virtual clutch feature that simulates clutch kick for drift.
Alongside these transmission-specific features, the MINI ECU provides a useful array of I/O for vehicle integration. It offers 5 analog inputs (e.g. for TPS, clutch position, engine temp, etc.), 2 digital inputs, and 2 general-purpose outputs. All MaxxECU models, including the MINI, also feature a fully configurable CAN bus interface, allowing them to send/receive data with external devices and ECUs. This means the MINI can easily communicate with your engine’s aftermarket ECU or OEM CAN network to gather critical signals like RPM, throttle position, and more. It even supports some OEM CAN protocols and OBD-II messaging for broad compatibility. Must use 500k bus speed.
Motorsport-Grade 8HP Wiring Harness
To complement the MaxxECU Mini, this bundle includes a Seems Legit Garage harness that makes installation straightforward and professional-grade. Each harness is meticulously handcrafted in the USA by our expert technician Shaun using premium materials. Key features of the harness include:
Top-Quality Construction: Built with TXL automotive-grade copper wiring and Raychem DR-25 heat-shrink sleeving for superior durability and protection. These high-end materials meet or exceed OEM and military specifications, providing excellent resistance to heat, abrasion, fluids, and vibration. This ensures the wiring can withstand the harsh conditions of engine bays and track use without issue.
Plug-and-Play Design: The harness comes pre-wired for the ZF 8HP, drastically simplifying installation. It’s essentially a plug-and-play solution, saving you hours of wiring work. All critical links between the ECU and transmission (such as CAN communication and power supplies) are complete.
Deutsch I/O Pigtail: For any additional inputs or outputs you want to utilize, the harness includes a Deutsch connector pigtail exposing all the MINI's extra I/O channels. This makes it easy to integrate things like paddle shift buttons, a brake pedal switch, an ignition cut trigger, or analog sensors – without any splicing. Simply tap into the provided pigtail connector to add whatever signals your setup requires.
With CAN: Simply tie the MaxxECU into the vehicle’s CAN network (500kbps bus speed required) and the needed signals (engine RPM, throttle position, etc.) can be shared digitally. The MaxxECU’s flexible CAN configuration means it can communicate with nearly all aftermarket ECUs and many OEM systems to grab the data it needs or to broadcast transmission data out. For example, you can have the MaxxECU receive pedal position, engine RPM, and vehicle speed from an existing ECU over CAN, and in return send out gear indicator or other data to a digital dash.
Without CAN: The included harness has you covered with analog wiring. You can wire traditional signals directly into the MINI’s inputs – such as an engine RPM signal, throttle position sensor, brake switch, temperature sensor, etc. The provided Deutsch connector pigtail gives convenient access to these inputs and outputs, so you can easily hook up the basics for transmission operation.
If your vehicle doesn’t already have a active CAN bus, we include a “short bus” CAN bus to create one. This has the proper terminating resistors to form a CAN bus between the MaxxECU, the 8HP’s TCU, and any optional CAN device like a digital display. This is especially useful on vintage cars, you can add a CAN-based dash to older cars using to display the physical signals you are sending the MINI.
