The 022 ECU has a different ROM chip from the 022D. I can't remember exactly,
but one has (I think) and 18 pin chip and the other a 24 pin.  There are other
differences, like the 022d has a metal shield covering the chip, where the older
ones have a plastic shield.

Don't know if the ECUs function and differently. It may just be that the later
ECUs have more efficient circuitry.

Todd
'88 Westy

David Jaffe wrote:

> Folks,
>
> In a week I'll have an 022 ECU I no longer need, because I'm waiting to
> receive an 022D with the Australian power chip in it,  so this not an
> academic question:
>
> I assume the O22D ECU housing itself and/or circuitry must be different from
> an 022 ECU, because to handle the Aussi chip, you can't use the 022.  So I
> wonder - is the original 022D chip programmed better than the 022 chip?  And
> if it is, can you plug it into an 022 ECU and make a better combined unit?
>
> Thanks,
>
> David Jaffe
> 1986 Syncro West'faux'lia
> 1982 Diesel -> I4 Westy
> Portland, Oregon