Front end vibration between 85-120 mph?
 

Have a 1981 911SC, with Bilstein HD shocks, turbo tie rods, Kumo tires, lowered and aligned for DE events with camber strut brace.

Runs very smoothly, however, between 85-120mph I get strong vibration in the front end - strong enough to make your eyeballs bounce around so one has trouble maintaining focus on the track - not good...Suggestions as to what to inspect, test or change?

Check your tires and balance first

+1, check your tire balance.

+2 but I suspect a flat spot.

Best,
Grady

I have lost my wheel weights on my racecar countless times. The tire guy at the track uses tape to try to keep them on, but it too melts, and the weights fling off.

They only stay on if I remember to put the aluminum tape over them when the tire guy is finished.

Drive at 84 MPH or at 121 MPH :)