I have always wondered why spark plug wires "naturally" hung low and in some cases even rest on the head.
Then I saw a spark jump from the middle of number one wire to the head with roughly 1/4 to 1/2 inch clearance between the two.
AHA! That might explain my occasionally loss in power. Put some new wires on and on a test run I could not duplicate the issue. The new plug wires are no where near the head while hanging naturally.
My old number one wire was scorched in the area that I saw the spark come from so I think all is well once more at "Aldrich Acres".
You can also get interference between two wires if they're turned the wrong way at the coil box.
like this Steve?