help for wheels and tires

[wzj519]

I am planning to upgrade my stock wheels to some Vorsteiner wheels and I am also going to run it with ACS springs on my 650 x-drive Grancoupe.

Currently, I have some questions about the wheels and tires here,

1. Is it ideal for me to run 20 x 9 et 31 255/35/20 at the front ? Is it ok to mount do 265/35/20 at the front instead of 255?

2. for the rear: 20 * 10 et 40 295/30/20 ? or Shall I go with 305 width at rear?

Also, is there any issue I should concern when I run it with ACS springs?

Thanks a lot.

Any opinion is welcome.