14-09-2021, 09:43 AM
Just add my 2p worth. I n the 1950s and 60s, I as a misguided youth used to "improve" the performance of my morris minor by over advancing the ignition, This resulted in pinking especially on full throttle acceleration. I would describe the noise as crackling tinkling, i.e. high pitched. I think the OP would have had pinking long before reaching 40 to 45 mph. I've never heard it on my 7, but I do get rumbling, i.e. low piched, when I forget to retard when accelerating from a low engine speed.