302 in my Z runs great, but I am hearing a high pitched whistle while it runs. It is coming from the carburetor inlet; when I place my hand over the air horn, it disappears. Is this normal, or does someone have an idea what could be the cause? I have a brief video but it's 18.3 MB.
If its coming from inside the venturi area it OK. The engine is pulling air and fuel through the carb circuits.
The Holley on my big block does the same thing. More noticeable since I pulled off the cowl hood flap for full time cool air, providing a noise path.