Help identify my rough running issues?

[byterrr]

OK next things next on the list of things to be done on my M20B20.

Since I got the car it has been running roughly and making a slight tapping (pinging?) noise towards the rear of the engine. It runs loudly and sounds like a tractor.
I've changed the timing belt and played with the ignition timing in addition to putting in brand new spark plugs and spark plug leads, changing the fuel filter and oil.
I fixed one leak I found in the vacuum lines. I haven't gone to the point of doing a smoke test. Is there anything I'm missing?

Here is a video. What does it sound like?

https://youtu.be/W8TRDyZoAyc

And when messing with the distributor timing

https://youtu.be/I7gQc_Dk_CM

[actletpone]

Have you inspected the valve train?

[byterrr]

I haven't yet, would that cause/rough running like this? I also doubt the injectors have ever been looked at but not sure if that's a potential factor

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[actletpone]

I haven't yet, would that cause/rough running like this? I also doubt the injectors have ever been looked at but not sure if that's a potential factor

Sent from my U using Tapatalk

With the tapping towards the rear of the engine I was wondering if your valves were out of adjustment, yes it could make it run rough, look for cam wear too, would be fairly obvious if it is that bad