Had what I thought was a vibration at about 90 k...turned out to be my tranny lock up kicking in and out rapidly...turns out that vacuumed ports are not all created equally. I was using a port of the side of the carb for my vacuum for my lock up. When I put a gauge on it I had to rev the motor up almost to 3/4 throttle to get the vacuum I needed. Tested a port on the front of my carb and it had almost twice as much vacuum just off idle. Switched my lock up port to the front and the tranny works as it should...Carb re- jet is next on my list...
Ported (vacuum taken above the throttle plates) VS non ported (manifold vacuum) taken below the throttle plates.