Here is what Z1 has to say
Extended Studs are required with the 10, 15, and 20 mm spacers. Always check to make sure the lug nut has sufficient thread available on the stud to secure it when installing any wheel spacer or combination of wheel spacers.
So maybe the 2.5mm and 5mm are safe?
https://www.z1motorsports.com/brakes...mm-p-3118.html
Sent from my iPhone using Tapatalk