What do broken head studs sound like?
 

I get a whistling at higher speeds, higher revs. Is there any chance this might be related to broken head studs?

I am almost afraid to do the valves since I've been reading about all of the broken head studs around this 'board.

John, not foolin'

Don't be afraid. It's sort of like not going to the doctor when you think you might have a serious health issue

once they break, they are incapable of whistling, so that wouldn't be it. what tune are you hearing? more info would be good. what key?

kind of like a cross between a jack-hammer in the distance ... and a noisy, annoying, small dog barking!!!

Do a test ... have a trusted assistant drive your car by in 2nd gear at 30 mph, while you listen at 50 feet away. BTW, it will be a distinctly un-911 sound! It helps if you have heard an old air-cooled VW Bus drive by with pulled studs go by ... same sound!

And, strangely enough ... kind of like all felines purring at 20 Hz ... the 'bark' seems to be at around 4 - 6 Hz, whether VW or 911, not the same exact note, but the same frequency rate of the head(s) banging at the cylinders!

i hope i never know...

I think they sound like this - ch-ching, ch-ching. Or "your name as it appears on the card and the expiration date please?" Sometimes they're disguised as a burly voice that goes "Grab your ankles. This won't hurt a bit."

looking is free. No assitant needed and only requires simple hand tools.

If you run with broken studs (this is heavily debated here) you could be okay or you could be out pistons, cylinders, and even heads in some extreme cases.

If you choose to just replace studs and do it yourself it could be under $500. If you take the opportunity to do a rebuild it could be $6,000 or more.

If you wait, the $6,000 "could" become $9,000+

Anybody got a good sound file we could listen to. I can imagine the sound but then again, I can imagine all sorts of things which aren't accurate.

Broken head studs sound like $$$$$$$$$$$$$

Of course, I'm cheap