bad case of alternator whine in my Miata

That can be a tough one to solve. From what I have read, if you had a BMW it might well prove to be impossible.

Here's a question that I bet Rob Schofield can answer: Can you solve an alternator whine problem by changing to a different brand/style of alternator? Even though that sounds like a drastic solution, you can buy a rebuilt alternator for a Ford or Chevrolet for less than $100, and that beats spending whole weekends ripping the wires out of your car trying to fix the problem. There are a few pitfalls... you'd have to futz around with the mounting hardware; you'd probably have to change the connector on the wiring harness that plugs into the alternator; you'd want comparable pulley sizes so the alternator ran at about the same speed as the original and so that the standard drive belt would work...

Does the noise problem originate in the alternator itself, or does it have more to do with the way the wiring harnesses and grounds are laid out?

tanstaafl.

"There Ain't No Such Thing As A Free Lunch"