hks_kansei wrote:if the OP does put in a new alternator be aware that NA and NB alternators are not interchangable.
The NA has a voltage regulator built into the alternator, the NB does not (NB regulates voltage via the ECU)
There is a simple mod from Miata.net for the NB to accept an Internally regulated alternator and bypass the ECU plus still have the voltage warning light functional:
I did this on my NB8A and it works ...