[papajam]

Those results don't seem too bad. But since your changing the plugs, cap and rotor, may as well change the wires too - especially if they're the 15 year old originals.

I knew this discussion would come up sooner or later. This is what I was taught.
High resistance ignition wires are used to reduce/eliminate RFI to the radio and onboard electronics and to a lesser degree, premature wear of secondary ignition components. Period. The resistance in the secondary ignition circuit, including resistor sparkplugs, has nothing to do with how "hot" the spark at the plug is.
To back up a bit, when the low voltage coil primary field collapses when the primary circuit is interrupted either mechanically (points) or electronically (optical, Hall effect), the collapsing primary magnetic field induces a high voltage from the coil secondary. This high voltage then travels to the distributor cap, thru the rotor and finally to the sparkplug thru the plugwire. For discussion, let's say that the voltage required to jump the gap at the sparkplug is 10,000 volts (although pre-emission engines with smaller plug gaps and richer mixtures need only half that). After the plug fires at 10,000 volts, there's still 9,999 something volts left over. So where does it go? Back to the distributor. But since the rotor is no longer lined up with plugwire tower, it has no place to go so it reverses direction and goes back to the plug. The voltage is too low to jump the gap at the plug so it reverses direction again, and again and again until it finally dissapates. RFI is the result of all this voltage bouncing back and forth.
Enter resistance plugs and wires. This added resistance results in much faster dissapation of this 'leftover' voltage virtually eliminating RFI. Although the added resistance forces the coil to produce a higher voltage to overcome this resistance, the voltage required to jump the plug gap doesn't change.
This brings up a common misconception thanks to clever marketing about high voltage (or high performance) coils. A high voltage coil does NOT increase the voltage at the sparkplug. It increases AVAILABLE voltage to the plug. A coil will produce only enough voltage to jump the plug gap and no more. But the coil may also not be able to produce enough voltage under cetain conditions. If, because of higher cylinder pressures under acceleration, wide plug gaps, lean mixtures, high compression or fouled plugs to name a few, the existing coil can't produce the required voltage to jump the plug gap, a misfire will occur. Under these conditions, a high performance coil may produce the required voltage to jump the plug gap preventing a misfire. So it's not that a high performance coil increases performance but rather it can help prevent performance loss.