Plug wire question

[gregh]

I've been trying to track a high rpm missfire & I started testing the plugwires for resistance. I'm using about a year old set of MSD blue 8mm Heli-core except for the coil wire, it was too short so I subbed in the Taylor wire from my last set of wires.
The Taylor wire measures 500 ohms & it's about 24" long so 250 ohms/ft. The MSD wires measure about 1100-1200 ohms/ft.
MSD site says 150-1200ohms/ft is normal but these seem to be on the edge.
Can the high resistance be causing the missfire?
The rest of my ignition is: Comp 9000 dist, Promaster coil, Hifire 6AL box.

Thanks for any ideas or suggestions.

 

[1981coupe400ci]

maybe its something simple like the sparkplugs? when were they last changed and what are they?

 

[gregh]

Accel plugs(shorties to clear headers), brand new, same as the rest of the engine.
I've pulled the plugs, they all look fine, no insulator cracks or anything else.