Hey guys new here so here’s the deal I got an 86 na recently had to put a new (junkyard) short block due to it blowing a rod. Put everything back together car started right up but has multiple misfires and runs like s*** I’ve checked and rechecked the timing multiple times I’ve tried different spark plugs and many other things and I still can’t figure it out also while it’s running when I unplug the plug wires of cylinder 1 3 and 5 there’s no change in the way the car runs