Whoa! Thats dangerous. Never had issues speeding with my 2019 CVT shitbox. Maxed it out on 160kph/99mph, never got issues with stability. Maybe because I got my shitbox lowered. There are no other modifications with the downforce other than the OEM+ vortex generators and crossbars. Most of the aftermarket mods are for off-roading. If you use your Crosstrek like that, consider modding it to speed on tarmac - not offroading.