Identifying noise?

[CaliTrav]

Hi all,

Hoping the collective brains trust can help solve this one.

I have a clattering noise on mid to heavy acceleration - usually when a lot of torque is being applied, so particularly noticeable uphill. The sound feels "central" so under the seats sort of area.

I can't reproduce it in neutral, and the noise isn't affected by speed or revs (it's more of a constant) - however, it disappears totally when I lift off the accelerator, but comes back when I push on it again. Beyond a certain rev point once I lift off, it doesn't come back (or I can't hear it)

I've replaced the U/Js in the prop thinking it was that but no joy. Video link below - any ideas?

www.youtube.com/shorts/Dk5b3Sko81Q

[oliver90owner]

First to guess. Engine/transmission mounts.

[kennatt]

could it be pinking perhaps,engine too far advanced,simply turn distributor to retard the timing,