The Transtronics ROMulator is a ROM Emulator. It can be programmed with just about everything you could want to put on a 28 pin EPROM (Learn about EPROM here). What exactly would you want to emulate with a device like this? How about the code and parameters an ECU uses. BEFORE YOU CONTINUE, read this page for a basic overview:


    Things you will need to use a ROMulator on a Z31:

  • 88-89 Z31 ECU.Compatibility information. (Please note: The ROMulator can be used on 86-87 ECU's with some additional modifications)
  • Install resistors and rewire the injectors for the 84-87 cars with low-imp. injectors.
  • Pocket Romulator. (offsite link)
  • Live Edit software: Free software (website), included in this .ZIP are config files and binaries from stock 1988 Z31 ECU's) If you encounter issues with the final version, to download the final beta version click here.
  • Time, and a willingness to learn!

    Things you will probably find very helpful for tuning/modification of the code:

  • Parameter locations in the Z31 binary files.
  • How to tune K value and void after installing larger fuel injectors.
  • Modification of the AFM, or installing another AFM to meter more air.
  • The Z31 binary archive. Submit your 'tune' and join a growing community!
  • The Z31 Performance Forum

    Ways to mount your ROMulator in the car:

  • Install inside the ECU case (non-trbo ECU only).
  • Install next to the ECU.
  • Think up your own?

    Please Note: At this time, actual power tuning past very far installation is beyond the scope of the information I am providing here. It's simply a matter of opinion that I should not share every last bit of information, but you should be allowed to learn for yourself by reading and using the provided software.

    1. It would be greatly to your advantage to purchase a wideband oxygen sensor with a data logger to help you tune.
    2. Timing adjustment should be done very carefully as it is critical in making reliable power. Ignition timing and air/fuel ratio are somewhat closely related; you should always keep this in mind.
    3. Performance tuning for electronic fuel injection systems borders on an art form. Provided the Live Edit interface, and a simple explanation of how the software/romulator combination works, any competent speed-shop "tuner" should be able to dyno-tune your cars fuel and timing maps for you. If you would like to learn in-depth tuning methods used by professionals to tune EFI, I suggest reading some books on it. I'm not an expert, I just know what I've read and that repeating it here would be a waste of my time when an absolutely excellent primer on EFI is available here for under $20. There is also EFI university for those of you whom believe you could make a career out of this and other forms of EFI tuning.

    Socketing the ECU and installing the ROMulator.

    88-89T ECU:

    Remove the "front" of the case:

    Daughterboard removed, EPROM circled:

    The hardest part is removing that chip. I would highly recommend finding someone with a quality solder sucker that you can pay to remove it (or pay to use their solder sucker as I did) and install a 28 pin press-fit socket in its place:

    Pocket romulator (Rom Emulator; you need model 1, not model 2!)

    Installed (note ribbon cable is actually plugged in backwards; don't do that):

    Bend resistors on daughterboard (turbo ECU only) to clear cable:

    Bend ECU case to clear ribbon cable:

    Load a binary file into romulator using transtronics software to test (note: either ECU has to be powered or ROMulator disconnected from the ECU to do this, it will not work otherwise as the ECU will try to pull power from your ROMulator):

    Use a PC to change settings and update romulator as needed using Live Edit:

    That's it, good luck.

    Go back.