Hellow doctors!
I'm back with some more problems... I recently started working on the ignition map (starting with a map found here) because I was still running the base map. The problem is, I can't tell when the engine is detonating. I already have some noises coming from the exhaust (heat shields and catalytic converter), so I know that at certain RPMs it's harder for me to tell... However, there's a specific rattling noise I'm not sure about... I think i was hearing this also before installing the MS3 but i could be wrong... it appears between 2,000 and 4,000 RPM and sounds like there are little pebbles inside the exhaust. I've attached a video and the map to help clarify.
Do you think it's just an exhaust rattle, or could it be detonation?
Thank you!

Additional Info:
-Miata 1.6 NA 1990, Stock 150k KMs Engine with a cold air intake and a catback exhaust.
-During the test i wasn't leaning out, I've putted a richer map for testing so the AFR in that moment was around 13.7
-Im currently running 95 Octane, I didn't try using 98/100 Octane avaiable in my country.

-Video:
-Ignition Map:

 

Don’t have great speakers for the video, but try taking 4 degrees out from 2000 and up, all loads.
see if the sound changes. If it does, great, if not, try 2 more. Personally, without a dyno, I’d pull at least 2 from that map above 2000.

 

Ty Boss, i'll try that and let you know asap!

 

What Curly said, pull timing and retest. I couldn't hear well in the video either.

 

For 95/91US octane it should not be detonating with those timing values. What do the spark plugs look like, are they peppered? Is it worse in higher gears or when going up hills? You can try reducing the timing or use the higher octane fuel. If there is no change I would inspect the manifold heat shield and catalytic converter.