This sounds ridiculous and the root cause could very well be "faulty equipment", BUT...

TLDR; I rebuilt my engine because of a bent rod (another long story, not necessarily relevant here), and yesterday - after the first successful start - I decided to check the base timing offset to make sure that it was as it was before. So, I whipped out my (super-cheap, all-plastic, completely sketchy) timing light (that I've used before). I set the MS to "Fixed Timing" set the offset to zero degrees, turned on the engine and flashed on the timing light. And...nothing...I saw nothing. So I shut everything down, grabbed some silver paint and painted the notches on the balancer thinking "They just weren't visible enough". I repeated, and...nothing. So I painted the line onto the face of the balancer thinking "The angles aren't good enough, so if I put the mark on the face, it'll be easier to see." I repeated and...the timing marks were down at 7 o'clock instead of being at 1 o'clock!!!

How the hell can this be?! The mechanical timing is right. The car starts and runs fine - no misses, no roughness at idle, probably smoother than it's been in a long time. But the timing marks are 180* "off".

FWIW - I'm using GM coils and a DIY harness. I'm using a MSPNP2 running wasted spark. The inductive coil for the timing light is on the #1 plug wire and I've tried every possible orientation of the pickup (it's not marked as directional as I've seen others marked). Nothing makes a difference, the marks on the balancer are 180* off.

I welcome any insight into this situation.

 

The outer ring of the balancer my have rotated in relation to the center. Put a screwdriver or something down the #1 spark plug well and verify you're at TDC when the marks say you are

 

The mechanical timing is spot on - screwdriver into #1 cylinder is at TDC when all the other marks line up.

I thought that the outer ring MIGHT have slipped in relationship to the inner mounting, but it looks to be EXACTLY 180* off. I'll unmount it later today and; A) see if the outer ring is slipping, and B) make a mark exactly opposite to the real timing mark and re-check with the light to see if timing is indeed exactly 180* off.

Right now, I don't have Superdamper, or Fluidamper money, but...DAMMIT!!

 

either the cams are facing inward instead of outward (lobes out), or you've got the coil packs mixed up. 2+3 is 180 out of 1+4.

 

Cams were facing out, and if I have 1/4 mixed up with 2/3 I'd expect the engine not to start at all, much less run smoothly. I'll recheck...

 

Waste spark and batch fire trigger for both phases.

 

Yeah, this. Or coils backwards.

I was helping a friend with the same issue. On his SBC he had the distributor 180 out and it was running fine. Because all the spark plugs were also 180 off

 

Okay, I don't know what I did, but it's working right now.

TLDR; I took off the damper pulley and inspected it. No cracks, no splits and the outer ring seemed securely fastened to the inner "core" (and the orientation of the locating hole to where I expected the TDC mark on the edge to be was correct. As far as the rest of the valvetrain, all of the marks lined up right and the cam lobes were where they were supposed to be (facing out on #1 at TDC). So I decided to make my own TDC marks on the pulley at 180* from where they were supposed to be. After measuring once and cutting 3 times with a file, I had some marks that were as close as I could get to "correct". So I buttoned everything up, connected my precision timing light and...EVERYTHING WAS LIKE IT SHOULD HAVE BEEN IN THE FIRST PLACE!!

I don't know how I "fixed" it, but it was good enough to set the base timing and go on with life.

Case closed...or is it?

 

Accidentally connected light on the wire for #2?

You sure work fast!

 

That was the first thing I checked!

PS - I'm tired of being Miata-less. Time to get back on the road again.