Ok........after 7 flights my engine is still acting up.....(its previous owner ran about 1 gallon prior to me, and I've run just under a gallon)

Tried riching it up, and leaning it out both high and low ends and combos.
Baffled up the motor and it now temps out between 140-170 (depending on the length of flight)


After about 5 mins of good running, the motor sounds like it drops a cylinder at anything above 1/2 throttle. Motor is not yet broken in
But the first 5 mins it runs great with lots of power.

Here's what I think...

1. Plugs are bad
2. Timing is off (but wouldn't that effect the whole flight?)
3. Ignition box is bad (it is raised up 3mm for airflow)
4. Motor is bad

Here's a pic of the plugs. Both of them have carbon build up just above the threads on the plug, on the smooth portion.. Both only have it on half of the plug. They don't appear to be too dark on the spark point. I ordered some new plugs incase, but was wondering some other peoples opinions first. (also what gap should the plugs be?) To me it seems odd to have the carbon build up like it is. But since I've never had a gasser I'd thought I'd ask first.