[135Pats]

My *guess* has always been that's it's the cylinder which sees the most direct airflow from the manifold. The stock intake mani is awful, i'd love to see flow distribution by cylinder but a quick once over shows that it's far from optimal. Cyl 5 is almost always the noisiest on these motors.

What do the other cylinders look like? What does the global timing curve look like? Some corrections across a single cylinder are not at all uncommon, and don't mean anything is "wrong" automatically.