Make sure your crank pulley bolts are tight, never hurts to check, one day i found my pulley wobbling, and creating vibration, turns out it was loose, and only had 3 fasteners in it, also i put a cheap balancer on and it, with a new pulley, solved the problem, but since you have a stroker, i assume the balancer is alright, but if it does it in park, i'd start inspecting.
good luck on it.
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Police package 5spd 90 Lx, Stock original motor, 3.27grs, BM fan, fms 10.5 clutch, D&D quadrant, and adjuster, ADS chip, 180 stat, mac cai, mac h-pipe, mac subframe connectors, ASP crank pulley, ripper shifter, 26x10.5 M/T sport pros welds. 246 hp according to analyzer 
Race weight: 3,120
E.t-13.57 with 26x10.50's e.t. streets. 1.88 60'
mph- 99.92 mph
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