Originally Posted by rv7charlie
Hmmm...'Trust, but verify' (?)
Ever try pulling the cap, removing and re-installing the plug, and rechecking the EI's reading? A simple resistance check, new & after, could be useful data, too.
IIRC, running a 'colder' plug makes conducting tip heat out to the head easier. Would that reduce the heat load in the internal resistor in the plug, extending life?
Yep, done that with regard to pulling and resetting the plug wires but have not pulled a plug to check it's resistance, as I said. No change was noticed.
Also, heat doesn't seem to impact the readings. The numbers do move around but the general trend is down. Meaning that one one flight, from startup to shutdown, the numbers are fairly consistent. Over multiple flights, the numbers trend downwards.
I have not hit the cylinder head with a laser thermometer but I imagine that once the plugs are up to temperature, which might happen slightly faster than the head, the readings are pretty stable.
RV-9 (Yes, it's a dragon tail)
O-360 w/ dual P-mags
Build the plane you want, not the plane others want you to build!
SC86 - Easley, SC