Now that I have installed the proper plugs in my 110 engine, the spark-plug thing makes sense. The older cars, such as the 114, 115, 116 and 123 models, came with resistors in the plug connectors, so non-resistor plugs were not necessary and would in fact create more ohmage than necessary - hence, a cold spark.

Bosch appears to be out of the business of non-resistor plugs; however, NGK still makes them for most applications and they can be found in many parts houses. Of course, the proper gap setting makes a world of difference as well.

Happy motoring, fellow Meche drivers!