Hey I wouldnt find an answer for the 981.
I know the 991.1 generation you need to be in dyno mode via piwis to get the thing to run to redline on a 2wd dyno.
But it looks like the 718 gt4 and 991.2 6speed has had users on the dyno with no problems as long as esc+tc are all off.

Is this the case with the 981 GT4 as well? Not sure if the 991 couldnt because it was pdk?
I want to dyno the car before/after tune but dont want to find out I need piwis again strapped up to the dyno....