Hey everyone, so starting a couple weeks ago a very strange popping noise started coming from the exhaust when I let off throttle. No it’s not backfires I’ve had a lot of those lol. The best way I can describe it is like a popcorn machine small and very fast pops.

engine is a gslse 13b with 2 msd 6aL for ignition, Weber 48 ida carb. It’s street ported and is basically straight piped.

I’ve tried new spark plugs and that didn’t work. Fuel pressure is good, just replaced the fuel pump, new fuel filters. So I’m really stuck hoping I can get some help.

Thanks