Steve,

If there are no vacuum leaks, I'd say it's normal carb aspiration going on, particularly if there's a small aftermerket air cleaner; the Rochester "B" on my old 235 Chevy stovebolts, particularly the ones with the small "truck air cleaner" (no silencer) whistled like hell, particularly at part throttle; I've grown fond of that noise- driving an AD Chevy would not be the same without it! wink


Frank McMullen
1941 Chevy dump truck
1949 GMC 100 pick-up
1954 Chevy 3600 pick-up
1955.1 4400 dump truck
1941 De Soto & other MoPars
1928 Model A F**D Special Coupe