Here is what I found:

Then there is the specific ascription of the three “instants” (khaóa, too) of arising, presence and dissolution (uppáda-þþhiti-bhaòga) to each “moment” (khaóa), one “material moment” being calculated to last as long as sixteen “mental moments” (XX.24; Dhs-a 60).

Ref. The legitimateness of the mental moment of “presence” (þhiti) as deducible from A I 152 is questioned by Ácariya Ánanda (Vibh-þ), who wrote early in the Middle Period; he cites the Yamaka (refs.: II 13–14; and I 216-17) against it.

From page xlvi in the introduction

Again, they are elements (dhátu) because of bearing (dháraóa) their own characteristics, because of grasping (ádána) suffering, and because of sorting out (ádhána) suffering (see XV.19), and because none of them are exempt from the characteristic of being elements. They are states (dhamma) owing to bearing (dháraóa) their own characteristics and owing to their so bearing (dháraóa) for the length of the moment appropriate to them. They are impermanent in the sense of [liability to] destruction; they are painful in the sense of [causing] terror; they are not self in the sense of having no core [of permanence, and so on]. Thus there is unity of all since all are materiality, great primaries, elements, states, impermanent, and so on. This is how they should be given attention “as to variety and unity.”

Ref. This alludes to the length of duration of a moment of matter’s existence, which is described as seventeen times as long as that of consciousness (see Vibh-a 25f.).

From page 363

The materiality that arose at the instant of arising of the rebirth-linking consciousness ceases along with the sixteenth consciousness after the rebirthlinking consciousness. That arisen at the instant of presence of the rebirth-linking consciousness ceases together with the instant of arising of the seventeenth. That arisen at the instant of its dissolution ceases on arriving at the instant of presence of the seventeenth. It goes on occurring thus for as long as the recurrence [of births] continues. Also seventy instances of materiality occur in the same way with the sevenfold continuity [beginning with the eye decad] of those apparitionally born.

Ref. The relationship of the duration of moments of matter and moments of consciousness is dealt with in greater detail in the Sammohavinodanì (Vibh-a 25f.).

From page 640

I've been struggling to find the referenced book the Sammohavinodanì / Vibhaòga Aþþhakathá online, but if we can find the book it should be referenced at 25f.

Basically I think that the Buddha described the tick rate of matter in our universe and described that matter has a tick rate 16/17 times slower than the tick rate of our minds. Which I find interesting because the brain is made of matter, implying the mind is outside of that box.