Yes you should replace them. I assume that you can use the same plugs that the 5.0's use. So go with copper, Autolight 24's and gap them at .035.
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87 GT, 4 inch cowl hood, long tubes headers,h-pipe,Flows,BBK cold air, Mass air,70mm MAF, 1.7's, 1" spacer,underdrive pulleys,Pro 5.0, King Cobra, Adj. fuel Reg., Lakewood Lift Bars,50/50's,subframes, 4.10's.
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Best MPH 104
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