Senior Tech Team
Join Date: Apr 2012
Location: Yerington, Nevada
Re: pinging under light load
Quietly reading, and I have a question, what type intake manifold is in place (sorry if I missed it in the topic), single, or dual plane?
Of course, a single plenum design will have all plugs fed by both barrel sides of the carb.
A dual plenum design would have two specific paths, one for cylinders 1, 4, 6, 7, fed frm one side of the carb, the other would be 2, 3, 5, 7 with the other side of the carb.
You mentioned a different primary air bleed per side of the carb, does it show different readings for the two sides, or only single different plugs, at random?
One of the things I used to do when I worked for Holley was to remove the set size air corrector's and bottom thread the holes, then use Allen set screws drilled to size in their place, so I could easily replace, and make my own air corrector jets.