Roughness On Run Up

[Bill Greenwood]

Yes I could had used a standard massive electrode type of spark plug, that is one that looks like in a car engine. The repair shop had a massive one in stock. and it is about $50 as opposed to $140 for the fine wire one. But I prefer the fine wire type and that is what is recommended for my plane and engine. My plane is turbocharged, I live at 8000 ft and I often fly above 16,000 ft. The fine wires work better at high altitude and they last a lot longer. Even my old ones look old on the outside but the electrodes look almost new after hundreds of hours. So you get you moneys worth from them. If I had bought the massive one, then the next day Id have gotten the fine wire one so really paid twice.
I don't know if the fine wires are do expensive because of precision needed or the iridium metal.
There's no evidence of anyone dropping my plug, it has been a year and 100 hours since the annual and was running fine. I didn't drop them or ovetorque them. As for as dropping, plugs are shipped in boxes and fed ex or ups or whoever drops the boxes. I have some doubts it the plugs are really that fragile. I have put a dropped one on the tester and it fired normal. I may send the plug to Champion to see what they say.