TECHNICALLY NO IT IS NOT SAFE. anything over 5mm you should install longer studs. Or go with a hug centric spacer like an Eibach or H&R Your going with almost 8mm (7.9mm) I really don't think any spacer should be used on stock studs that is over 1/4". Then you say what's the point Your just aren't getting the bite you should.
You'll have all these people that say I run them which is fine let them. Many people have done it. You asked and I'm telling you no it's not safe.