What is this engine noise?

[rturbo 930]

Sounds like a valvetrain noise to me. Valve float? The noise starts about 3 seconds in, you might need headphones to hear it. Seems to only occur at higher RPMs, around 4k+.


https://www.youtube.com/watch?v=UtjNLgvcIQU

[nando]

Without any context, it's impossible to tell. camera noise? you moving around in the cabin? keys banging around mid-corner?

I didn't hear anything concerning in the video you posted, but I couldn't tell what I was listening to either. Maybe do it again with the camera pointed at the tach?

[rturbo 930]

I was afraid it wouldn't pick it up well enough to hear. Unfortunately, I don't really have a better way to capture the sound. Maybe I'll have to pick up a mic.

It's a high pitched sound, sounds kinda like like something gets out of sync at higher RPMs. I'm imagining it's a valve/rocker issue. You can hear the sound start at the 3 second mark if you listen very carefully, and it changes pitch around 5.5 seconds. Seems to be more susceptible to doing it if I hold RPM.

Anyway, guess I'll shop for a mic to stick in the engine bay to see if I can record it better. Also, it's occurring to me that I probably don't have to be driving for it to make the noise. Could probably just free rev it. I'll see what I can do tomorrow.