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Discussion Starter #1
So I’ve always had an exhaust pop noise that kind of blends in with the overall exhaust noise. I always thought it was a bad muffler that was extremely rusted and had a hole in it. I recently replaced my mufflers and pipes all the way to the H pipe. And the exhaust sounds better but I’m still getting that popping sound, almost like a deep rattle. I’ve narrowed it down to the left exhaust pipe. I’ll post this video, not sure if anyone can hear it. Car seems to be running fine tho.... here’s a link if anyone has any ideas or if it sounds normal....

 

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So I’ve always had an exhaust pop noise that kind of blends in with the overall exhaust noise. I always thought it was a bad muffler that was extremely rusted and had a hole in it. I recently replaced my mufflers and pipes all the way to the H pipe. And the exhaust sounds better but I’m still getting that popping sound, almost like a deep rattle. I’ve narrowed it down to the left exhaust pipe. I’ll post this video, not sure if anyone can hear it. Car seems to be running fine tho.... here’s a link if anyone has any ideas or if it sounds normal....

Does not sound normal. I'm thinking a valve might be hanging up. Are you running hydraulic lifters?.Might have one a little tight. I like 1/2 turn after clicking stops.
Try pulling the plug wires one at a tine on that bank and see if you can isolate to which cylinder is doing it.
 

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The pop is from unburned hydrocarbons collecting in the exhaust and then being ignited. Your idle air fuel ratio is probably way to rich and could cause this. To lean can also cause the popping.
 

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A couple thoughts on what could cause this....

a. Exhaust leak at the manifold/header flange sucking in oxygen-rich air and igniting unburned HC's.
b. Inductive crossfire between #7 & #8 cylinders due to improper spark plug wire routing.
c. Poor fuel distribution/atomization caused by dribbling discharge nozzle, vacuum leak affecting one primary, PCV plumbed into an intake runner.
d. Ignition misfire caused by deteriorating/defective spark plug, spark plug wire, cracked or carbon-tracked distributor cap, etc.
e. Sticking exhaust valve.

I'd throw a vacuum gauge on it and see what the needle tells ya.
 

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Discussion Starter #6
So I’m gonna replace my plug wires and spark plugs next weekend. I also have had bad leaks at the donuts from the exhaust manifolds. But I thought I patched those up. My spark plug wires were tied together with zip ties so maybe that was causing inductive crossfire. If I keep driving like this will it ruin the engine?? Seems to be driving fine. Eventually I want to switch to hipo manifolds and attach the h pipe to the pipes I just replaced.
 

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Discussion Starter #7
I also had the carburetor rebuilt about a year ago and took it back to get dialed in about 4 months ago.
 

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So I’m gonna replace my plug wires and spark plugs next weekend. I also have had bad leaks at the donuts from the exhaust manifolds. But I thought I patched those up. My spark plug wires were tied together with zip ties so maybe that was causing inductive crossfire. If I keep driving like this will it ruin the engine?? Seems to be driving fine. Eventually I want to switch to hipo manifolds and attach the h pipe to the pipes I just replaced.
Get some "real" plug wire separators and arrange the drivers side so they are in the following order from front to back and #7 & 8 don't come close to each other or cross each other.

7---5---6---8
 

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Discussion Starter #9
So I noticed that when I have the car on park I get the popping noises. When I have the car on drive it doesn’t really pop. It’s not noticeable. And now the last couple of times I’ve hit a bump the car turns off or wants to turn off. Fml.....
 
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