It came time to to find some spark plug wires for my retro mod SN95 Ford Racing X Head 427.  The 427 was based off the Boss 351W block, so I needed wires that were compatible with the 5.8 liter engine.

Prior experience showed that the “pre-cut” wires led to misery.  There was always enough wire; there was always too much wire.  So my great looking engine was covered with spark plug wire spaghetti…no one made enough wire retainers to avoid the inevitable.

MSD Ignition 31323 Spark Plug Wires

The final selection was the MSD Ignition 8.5 mm Super Conductor Wires (31323) .  The wires are a “universal” set, which means that you must cut-to-fit.  The spark plug side boots are gray silicon rubber.  More importantly, the spark plug ends are bendable, which keeps the silicon rubber away from the headers.

MSD Ignition Silicon “Bend-to-Fit” Spark Plug Wire Ends

The distributor ends  are the “cut-to-fit” portion of the deal.

MSD Ignition Distributor Side 8.5 mm Wire Ends

Assembling the Plug Wires

You must buy two items to handle the cut-to-fit spark plug wires:

1. An Accel Wire Crimping Tool (170036) – It will be the best investment that you ever made.  Thank me later.  This tool is a bit incredible in that it has crimp dies for both MSD spark plug crimps.
2. MSD Spark Guard Dielectric Grease – The distributor-side boot will slide on very nicely once the grease is applied.  If you do not use the grease, you will spend  a frustrating afternoon fighting the wires.

MSD Ignition 8.5 mm Super Conductor Wires (31323) have great instructions for the cutting and crimping sequence.  The Accel crimper will do a great job of attaching the distributor-side crimp terminals.  The quality of the MSD wires are beyond reproach.  MSD advertises 40 to 50 Ohms resistance per foot…they deliver.

I performed a comparison of the resistance between another set of cut-to-fit spark plug wires: Ford Racing Wire Set M-12259-M302.  The Ford Racing wires have a simple crimp compared to the MSD wires.  It was so simple, I really questioned whether the crimp would be effective.  It was not.  I compared the resistance of the MSD wires to the Ford Racing wires.  The results are shown below:

As you can see, the ford Racing wire resistances were all over the place.  The MSD results were dead consistent and in line with their 40 to 50 Ohms per foot claim.  Case closed.