MaxxECU GEN2 RACE pinout and specs

Checked against the maker's documents 27 September 2026

MaxxECU GEN2 RACE is a 136-pin wire-in MaxxECU ECU on 4 connectors: MX1 (34 pins), MX2 (34 pins), MX3 (34 pins) and MX4 (34 pins).

It has 16 injector outputs and 12 ignition outputs. The injector drivers are peak-and-hold, so low-impedance injectors run without a resistor pack. The ignition outputs are logic-level. Smart coils plug straight in; dumb coils need an igniter in between.

There are 8 dedicated trigger inputs, each happy with a VR or a Hall sensor. Two knock inputs cover both banks of a V engine. It has 2 onboard wideband controllers, so a sensor wires straight in. The MAP sensor is built in.

It has H-bridge outputs labelled for an electronic throttle, so drive-by-wire runs from the ECU itself. Two CAN buses handle dashes, PDMs and expansion. Eight outputs can switch 12V as well as ground.

Spec sheet

Which builds it suits

Of the 58 swap presets in the planner, 28 fit as they are and 29 fit with add-ons; 1 does not fit at all. The add-on it asks for most often is an external igniter. Where it falls short, it is usually not enough knock inputs. The planner fills anything a preset leaves open with its ordinary defaults, so your own build may land differently.

It runs the GM LS6 (Gen3 5.7 alum), GM LSA (Gen4 6.2 alum, S/C), Nissan VQ35DE Rev-Up (2005-06) and Subaru EJ/FA EJ25 turbo dual-AVCS (EJ257 2008+) presets with nothing added. The Ford Modular 4.6 2V (SOHC) needs an external igniter. The BMW N54 (3.0 twin-turbo I6) needs a direct-injection driver module and an external igniter. It can't run the BMW S54 (3.2 NA I6, E46 M3): not enough knock inputs.

Plan a build around the MaxxECU GEN2 RACE

Pin table

By connector: MX1 carries 4 injector outputs, 4 ignition outputs and 4 trigger inputs; MX2 carries 2 injector outputs, 2 ignition outputs and 2 knock inputs; MX3 carries 6 injector outputs, 6 ignition outputs and 8 analog inputs; MX4 carries 4 injector outputs, 4 trigger inputs and 1 CAN bus.

Other MaxxECU ECUs

The closest MaxxECU unit is the MaxxECU GEN2 TRACK. Against it, this one has 16 injector outputs (the GEN2 TRACK has 8), 12 ignition outputs (the GEN2 TRACK has 8) and 136 pins (the GEN2 TRACK has 102).

• MaxxECU GEN2 TRACK

Source: MaxxECU documentation for the GEN2 RACE

Always verify against the manufacturer's manual and your tuner before wiring.