I sandblasted my OEM TCT but after re-installation, there was a fluttering sound from the engine, which is noticeable when the top is closed. During open top driving, I can't hear it. I replaced the TCT with the Billman GenX TCT and the sound is still there. Is this sound normal for S2k's? I heard the fluttering is a sign of timing chain loading that can make the chain fail, so I want to make sure this is normal. Thanks.

Here is the Youtube video but the fluttering is not captured as well as in person.

 

Fluttering is not a sign of timing chain loading.

It almost sounds like a crack in the exhaust somewhere.

The noise you are referring to, does it make it through most of the video?

 

There have been several threads on this, including one by me, and no one seems to figure it out. Mine it comes and goes.

 

Yes, it makes the noise through most of the video. I can hear it above 3000 rpm. Below that, I can't hear the fluttering.

 

Check your catalytic converter.
I have a similar sound arount 2500-3000.