Paul, very interesting.  Of course, any spark plug at 200K ohm would have problems, were the Champions old?  I have no problem with my Champions, which have 240 hours on them -- other than the high price, of course.  Mine tested all under 5K ohms at 120 hours, I haven't tested since (been flying a lot since annual!!!).  Charley Brown
Legacy 240 hr

On Jun 13, 2013, at 6:36 AM, Paul Miller wrote:

IO-550 in the Legacy was having a horrible time LOP with the Champion RHB 32E.   I ended up testing the resistors, found them all failed, some in the 200k  ohm range.   I did a test using some of these surplus BG-341 (RHB32E equivalent) plugs and eventually went to a full dozen.  In flight LOP with a mag off resulted in complete smoothness.  It was like night and day.  Calls to Champion went nowhere.  These plugs have about 200 hours now, they cost me $9 each.  I have not yet tried Tempest but at this cost, I'm in no rush.  Champions would now be my last choice.  Paul, Legacy, Calgary
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