I have the same vibration on my 5.0.
Can you make the vibration on neutral?????
My engine mounts bolts on block are not tightened correctly and i don't know how this happen...
hope this could help.
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84 Capri RS,Stock long block, Melling Cam 512,512 lift-230,230dur @.50, Performer RPM intake, Flowtech long tubes headers, Stock carburetor, 84 T-5, SVO Aluminum Driveshaft, 8.8 with FRP 3.73, Drag radial’s T/A 255 50R16. BEST ET : 13.45 @ 102 MPH Best 60FT 1.89
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