Unlike spark plugs firing inside an engine, SparkViz allows you to see all four plugs firing simultaneously, enabling you to compare the spark plug arc quality (colour and strength) over a variable RPM range.
SparkViz is ideal for:
Testing old or newly adjusted spark plugs over a variable rev range (up to 12,000 rpm!).
Identifying weak spark plugs
Identifying poor arcing at low or high revs
Seeing and compare for yourself the arc quality of various spark plug makes and brands