I apologize if I’m in the wrong place … hope someone points me in the right direction?

Just bought new 2021 230i coupe/rwd ... rear differential final drive axle ratio of 2.81, am looking for help that will assist in deciding best solution to lower the ratio and get into the high 3’s or low 4’s 0-60.

Find another differential that will bolt up or replace with new ring pinion and if so ... best ratio … maybe something closer 3.91?