Exhaust Noise

[Jims65cyclone]

I'm getting an annoying popping and crackling noise from the exhaust when the car is decelerating with the engine holding it back (4-speed). It's more noticeable at slower speeds vs. expressway speeds. No loud backfires, just popping and crackling. Engine is 302, cast iron headers, dual exhaust with no X or H pipe. What's the cause and cure?

Jim

[A/FX]

Check for an exhaust leak, maybe a cracked manifold?
I had a header gasket leak and had the same issues you are experiencing, new gasket problem solved.

[Joe Travers]

My pipes crackle lifting the throttle and coasting @ 70 mph.
Had a 8N years ago that popped acorns out of the tailpipe first startup in Spring

Joe

[Jims65cyclone]

Check for an exhaust leak, maybe a cracked manifold?
I had a header gasket leak and had the same issues you are experiencing, new gasket problem solved.

I've noticed what sounds like an exhaust leak at the donut gasket where the manifold connects to the exhaust pipe on one side. I'll check that out. Thanks!

Jim

[Sugarmaker]

Jim,
I had to replace both of the donuts in the 289 manifold to down pipes. The old donuts were long gone! It was not one of the most fun jobs. But should be a good project for your car to be on your lift! Might solve the noise issue?