Gerald Loyd
Active Member
I never hear about anyone using auto spark plugs with magnetos. Why not use them. A set of 8 auto plugs cost a lot less than one aircraft plug.
Not uncommon in racing engines to run magnetos and auto plugs, I have many times.. But, the heat ranges are different, the application is different and the plug life is short. Aviation mags have far less output than auto racing mags. Racing mags can jump a much larger gap. I've seen them jump over a foot on the test stands. The smaller auto plugs would be more susceptible to lead fouling with an aviation mag, not so much with an EI. Not a lot of pros to the cons.
Some of the auto plugs, such as the BR8EIS have very high resistance, about 5K ohms. Isn't that hard on the mags, especially the coil?
The Autoilite 386's are not resistor plugs, and do not have high resisitance.
Vic