Does anyone have any ideal where or what kind of ecm to use on a rx8 with a 13B cosmo engine trying to find a plug and play one

 

Assuming you have a 2004 - 2008 S1 model; the earlier Adaptronic “Select” is a piggyback ecu, which includes the prewired patch harness. I believe some people piggybacked the Microtech ecu on there, sometimes under a different name. Which you can piggyback many aftermarket ecus with a patch harness to wire in various features around the factory pcm

Patch Harness (04+ RX-8)

with the understanding that the end result will not pass an OBD2 emission requirement.
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