The major change expected is the addition of a manual transmission option for the GT3. This means buyers will not have to opt for the expensive and exclusive 911 R in order to get the high revving naturally aspirated flat-6 engine paired to a manual.
Porsche will likely offer a slight power bump as they always do but the 3.8 and 4.0 liter engines are expected to carry over with some minor tweaks to the 991.2 GT3 and GT3 RS models. There is a rumor we might see a 4.2 liter GT3 RS. We will know more as the vehicle gets closer to its release date.