My friend has a '57 buick with a stock V8 that has an aftermarket Holley 4bbl (not sure on the size or model yet). It makes a very annoying whistling sound under moderate acceleration. Once you get over about 20 mph it goes away.

Now, I'm no carb guy, but I've never come across this sort of problem before. I've tried some basic stuff like making sure the carb was tight (and making sure I didn't run out of threads on the carb studs), running the engine without the air cleaner (just made the noise louder because it wasn't muffled by the air cleaner), checking the throttle plates for alignment and tightness, and checking for vacuum leaks (open ports, disconnected or damaged hoses, etc.).

At this point, I have no idea what to do next. The carb is less than a year old and the car runs great, so it would be hard to convince the owner to replace it again.

I am almost considering installing one of those BS snake oil Tornado intake thingies to create a little turbulence in the carb, but I'd hate to give money to a company like that.

I just don't know. Any help would be greatly appreciated.

Thanks.
Joe G.