It starts about 4 seconds in, when I step on the gas pedal -- headphones make it a lot easier to hear.

https://youtu.be/Q5jzyhQaxvg

Is it ping? If not, what could it be?

Sounds like intake roar to me. Do you have a stock air cleaner?

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Joshua

Yeah, I hear the tingling ping of light detonation, & that can have a number of causes. Forgive Me , but what are the details of Your ride, miles on engine, mods, timing etc.??

I doubt he has 1500 miles on a very fresh rebuild, I think it's a 74dart, original engine. He just swapped to a super 6 as what I can explain best as the "next stage" modification brand new Chinese clone carter BBD.
He was having issues with the original carb and rebuilt it, played with jetting and such before going to the super 6 setup.

OK, I saw the odo in the vid, but that's why I asked. So all of the usual culprits & related questions;
Cranking compression
Initial & total initial+mech. spark advance
Fuel pressure
Does it surge
running eng. temp.
Color of spark plugs clean/white
Octane of the fuel & poss. alcohol content
Camshaft OE or ???
Carb installed as delivered?(many have jacked up float levels etc.)
Exhaust free flowing & good shape
Any signs of a vacuum leak anywhere

I am not hearing anything alarming...Tho it could be my hearing.

Can you get it to make this noise at any other speeds or engine loads?

Have you got a tachometer and vacuum gauge in the car to tell you what the corresponding RPM and amount of vacuum is being pulled when you are hearing the noise?

I had an '81 318 Chrysler that made the same noise when accelerating, after the lock-up torque converter engaged. Don't think it will harm anything, but back off the timing a couple degrees and see what happens?

I don't have a tach, but I have installed a vacuum gauge and an AFR gauge. The noise occurs when the engine is fully warm, vacuum is less than about 5 inches and RPM is about 2500 or higher (as best I can tell by ear). It's especially bad going uphill, and does seem to be worse when initial timing is more advanced.

I wasn't really trying to start a new troubleshooting thread yet. I just wanted to verify that what I think is ping is actually ping. The noise I'm talking about is the faint metallic rattling sound. I can't hear it in the video unless I listen with headphones, but I can sure hear it in the car.

In headphones I hear it plain as day: yes, that is ping.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Sounds perfectly fine to me.... head phones as well

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"It's not the honors and the prizes and the fancy outsides of life that ultimately nourish our souls. It's the knowing that we can be trusted, that we never have to fear the truth, that the bedrock of our very being is firm."
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