JohnL455 wrote on Tue, 14 September 2021 13:27

Mine will “burble” during long engine braking, but I have my exact GM copy exhaust system installed so it is barely noticeable.
I suspect your idle mixture may be adding extra fuel causing this to be more pronounced. If you have 3” stainless this may exaggerate it. Correct mixture is balanced best idle just at the lean drop edge. “Emissions” setting would be 25 RPM lean drop per side to get 50 RPM lean drop.

I have no way to check or test emissions, should I adjust the carburetor? How do I do that?

BTW, I have no idea what this statement means "Correct mixture is balanced best idle just at the lean drop edge."


Larry