older versions of Hondata worked with OBD-0 honda motors, they were classified in stages and before the whole s100 systems. You might be able to find someone selling those old boxes on ebay or other honda forums, but dont look towards Hondata for support.
The other alternative to look at is what Domino suggested, and go the DIY route. You can buy a pre-converted ECU from people on the net and then all you need is the correct wiring to connect to your laptop and a wideband O2 sensor and your ready for some custom tuning. The software i would suggest that you look into is TurboEdit,
www.turboedit.org. its a completely free software and includes some base rom for easy tuning.
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