ae86 ROM

Want to see the ECU CPU ROM data on the 4A-GE AE86?

2D fuel map and simple 3D ignition map
It was running on Motorola 68series CPU.

Check the modification date and time of the file ;-)

You can download it from the following.
ECU CPU ROM data for AE86 4A-GE download here
Unzip the zip file and open the file with a binary editor.

Link policy
Please link to this page.
Do not directly link to the file.


Two major categories of electronically controlled engine tuning

There are two types of engine tunes: genuine ECU and engine management.

Genuine ECU Tuning
A tune that adjusts the fuel and ignition timing according to the increase in intake air volume and muffler replacement and changes the limiter.
Several tens of horsepower gain are possible even with a naturally aspirated engine.
It is easy to power up more than 100 horsepower with a turbo car.
The working time is very short, so the cost is low.
Demonstrate stable performance as a whole.
Vehicle functions such as auto cruise and meters can be used continuously.
Since the genuine ECU is not intended for modification, there is little freedom.
Tuning requires changing data in the internal ROM or additional electronic parts.
Even if you rewrite Flash data, you cannot receive the automobile manufacturer’s warranty.

Engine Management Systems
Power-up freedom is great.
However, the original function of the vehicle can hardly be used.
It is also difficult to operate genuine meters.
The cost is high, and even if it is simple, the cost is close to $ 1000 with only hardware.
Even with DIY, if you include wiring and sensors, you need about twice as much.
High-end engine management costs more than $ 500,000 a year, including contracts for engineers.
Working time is overwhelmingly longer than running time.
This road is very difficult, but the return on success is great.
It is recommended to choose a race-only vehicle.

Neither can exceed the limits of the hardware.
It controls the optimum fuel injection and ignition timing for hardware changes such as mufflers, turbochargers, and cams.

D Jetronic MAF sensor less System “MAFLESS Tuner” Coming Soon

Vehicles that use AFM or MAF sensors in race cars are very rare.
The engine management system basically does not use MAF.
MAF is the resistance of intake air and loses horsepower.

  • Eliminate the intake air resistance of the MAF sensor
  • Higher response than MAF sensor
  • Remove horsepower limitation from MAF sensor
  • Increase / decrease of fuel injection amount can be adjusted
  • Map control equivalent to Engine Merger Systems with existing ECU
  • No limit to the air intake diameter
  • Multiple throttle is possible
  • Throttle density (throttle speed) method can be used in addition to D-Jetronic
  • 3D setting function of fuel injection amount by MAF input of ECU
  • Compatible with MAF sensors (hot wire, mechanical airflow) up to 5V Output
  • Two types are available: naturally aspirated and turbo engine
  • Automatic setting using existing MAF sensor
  • Password protection for setting data
  • Data logger function for intake pressure, rotation speed, and throttle position
  • USB Type-C connection, Windows software control

MAF sensors (mass airflow sensors) are installed in most electronically controlled engines.
The MAF sensor usually has a power supply of 12V and an output of up to 5V or less.
(Sensor output is 1V to 4V during operation)

MAFLESS Tuner emulates the MAF sensor by adding D-Jetronic control with a pressure sensor and a 3D map of the number of revolutions, and α-N control by the throttle position.

Click here for MAFLESS Tuner Products page