I have a 650 DP that has a whistle that changes with throttle postion. I'm guessing that the throttle shafts are worn. It runs like a top, so I guess the other metered vacuum leaks have compensated for it due to my expert tuning skills. I'm kidding about the last part.

 

It's not really a high pitched whistle, it's more like an air compresser blowing or sucking air. I just had the carb. rebuilt with all new parts

 

Here's pics of the Carb.

 

i just had the same exact problem that i fixed yesterday, i swapped out the base gasket (even though it looked perfectly fine) and it fixed right awayy

 

Ok I will get one today. How tight did you tighten the carb to the manifold?

 

til it ogt kind of hard to turn, and then a little more

 

Ok, I'll let yall know if it works.

 

in case you do not know your vacuum under your front bowl is open.... old pic i hope?

 

Haha, yeah old pic, it has a vacuum cap on it now.

 

Alright, I installed a new carb base gasket and the noise was still there. So I took off the air cleaner stuck my hand over the top of the carb and wah-la the noise was gone. Of course the truck stalled out, but it was the carb sucking in air. That crossed my mind a couple times but the noise is loud, I guess that 460 needs to BREATHE!

Thanks guys!

 

You may want to try a 1" carb spacer to see if just moving the carb up off of the manifold will help eliminate the whistle. It could be just the aerodynamics of the carbs baseplate openings to the manifolds inlet design causing the whistle. Most likely the added volume with the spacer will help power numbers as an added benefit. Todd

 

I will look in to that. Thanks

 

Are you running a 4-hole gasket on a divided-wall or open plenum intake pad? This can cause weird sounds sometimes.
EDIT- just seen the picture and it looks to be an iron intake. Make sure the gasket is a 4-hole 1 11/16" hole size or the stock 4300 gasket and not a 1 9/16" 4-hole gasket if it is a 68-73 intake manifold.

 

Double post

 

I switched the one in the pic above to the one in the pic below from Mr. Gasket.

 

Looking at this 1" carb spacer. Anyone use this one?

 

Use a four hole 1" spacer on a stock intake or gas will puddle on the dividers under the carb and possibly cause irratic idling characteristics.

 

I have a performer 460 intake manifold

 

Make sure the carb gaskets are flush on the inside of the passages or you'll get your whistle back.

 

Will do!

 

Sorry to be a nit picker but I think using teflon tape on your fuel lines is not recommended.

 

lol, It wasn't sealing correctly, but does now.

 

Fuel lines seal on the tapered part so teflon tape on the threads does nothing. Unless you count the little pieces that make their way into the carbs jets.