My oh my, I didn`t know until now how difficult and complex it is to choose a plug for my engines, it is almost rocketscience it seems[sm=lol.gif]

I run OS F in all my fourstrokes, they might cost a $ more than others but so what? they last forever, I think I have never blown one of those.
In my twostrokes I use whatever I have at hand, mostly OS 8, 5, 3,also the F, Towerplug, Sirio`s, Rossi`s, Mc Coy 59, ASP, and propably lots of others. After a needle tuneup I can hardly tell the difference between them in the air or on the ground (car, boat)

I did some peak rpm testing a couple of years ago and in my engines rpm never varied more than max 300 rpm peak no matter what plug I used, so I think for casual sportflying it really doesn`t matter that much