It was absolutely revolutionary back in the 1980s when Diamond Marine introduced this programmable ECU. Diamond Marine would program and reprogram the ECU according to the customer's needs.

These boxes are especially rare today, but it's my understanding that there are a few that are still in service! And although it was originally designed for the 2.4-litre fuel-injected Mercury Bridgeport, these ECUs were subsequently programmed for use on the 2.5-litre series of engines when they were introduced in 1991. Interesting to note that back then, the Bridgeport and early 2.5-litre engines used analog ECUs.

This was not only the first programmable ECU, but it was also the first digital ECU for Mercury engines. I'll have more details on this (and a nice look inside) on a follow-up article shortly!

Greg

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