Maybe too much total timing. try backing off to 36 deg total. Also see if a plug wire could be breaking down. hook up timing light and switch clamp from cyl 1 then 5 then 7 etc and see if they're all firing! Hope it helps wagondude
427cutlass said:ya i changed timing to 36, checked and set valves, changed springs on distributer, rus a bit better, but still has light miss, think im gonna put new wires on......