So, in the midst of fixing a few things on Betsy, I was trying to troubleshoot an intermittent problem with rough -and sometimes VERY rough- running. Turns out at least one of my spark plug wires was intermittent when cold. Can't remember the last time I changed them, but didn't figure it significant as this truck does <10,000km/yr.

I purchased replacement wires ahead of time. I have no idea what these are worth and thought $35cdn from the wholesaler was a good price (it was).

The problem is that, with wires this cheap, you run into some problems:
-cheaper wires have a higher resistance/foot, usually around 1k ohms/foot
-cheaper wires create ALL SORTS of radio frequency interference

I landed up with a $75cdn set from a performance place -the same place I bought my Holley- and these have a ferro-resonant core. All the radio noise went away. This is significant to me as a Licensed Radio Amateur, VE6VPD.

-More expensive wires have lower resistance per foot (300 ohms) and should pass more spark along from the distributor to the plug.
-You can purchase racing grade wires at 50 ohms/foot if you really want to. I asked the guy behind the counter if the price difference would be saved in gas... he smiled but could not answer definitively.

Lesson learned, and shared. Spend money on your wires.

 

Just buy Motorcraft...

 

I am really happy with the top-line AutoZone wires. Every 30 to 50 thou I walk in, drop em on the counter, and walk out with a new set for FREE! Lifetime warranty in a great thing!