vibration prob, please help

[tandk22]

Thank you we may have to pull it and check it out. The motor was in the car when I bought it. More reason to check. It just strange it gets so pronounced around a 100mph. The vibtation might be there at the lower speeds and high rpm. You start to feel it in fourth but gets bad in 5 and 6th as you approach that mph range. Thank you

I had a vibration in my 383 stroker after having it rebuilt and the shop failed to balance the crank upon reassembly. It had a vibration between 1800 and 2100 rpm. Had the motor reworked and it went away. Not saying that's your problem but sounds like you have checked everything else. Good luck.