does a jagged plot on a dynograph indicate the presence of knock?

 

It can - but it can also mean a lot of other things

e.g.

Hole in timing map
Miss fire
Boost issue
rich or lean spot

etc

 

spark plug gapping too!

I had mine tuned on the dyno this weekend and the gap was to big for 32lbs so we had to gap them down a tad and the problem went away...btw, the log during the dyno didnt show any instance of knock at all

 

If the dyno graph is time based instead of rpm, it won't be as smooth as the rpm based maps. OKIX graph had only 1 -2 very intermittent counts, but graph is time based and isn't nearly as smooth 'appearing' as an rpm printout.