I have a 91 n/a, street port, AFC Neo, exhaust, intake...okay, so here is the issue, I just put new brake rotors on the front and rear, and I just now noticed, that when I hit 80mph, I got really heavy vibration and it sounds as if it is coming from the passenger side front. It does not do it at any other RPM range, so hi revving isnt the issue? Could it possibly be out of balance tire? Let me know what you think, I run on 17's installed about a month ago and no problem until recently? Thanks

 

Do you have hub centric rings? One fall out when the wheels were off?
Switch the front to the back and see if any difference.

 

ill swap em, but they are lug centric...

 

Check the motor mount while you're at it.

 

i was thinking that, but would me being able to rev freely in all RPMS diminish if it was a bad engine mount?